Shop All Antibody Labeling Kits (Conjugation-Based)

DyLight™ 755 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 755 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 755 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins—the amine-reactive DyLight 755 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 755 is a near-IR fluor that is invisible to the naked eye but increases the staining options when using infrared imaging systems. DyLight 755 has spectral properties that are very similar to other near-IR dyes, including Alexa Fluor™ 750. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 755 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 755 NHS Ester:

High performance—DyLight 755 replaces Alexa Fluor 755 for near-infrared staining
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting, or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 755 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 755 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 755 NHS Ester
DyLight™ 755 Microscale Antibody Labeling Kit

DyLight™ 755 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 755 Microscale Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 755 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG—the amine-reactive DyLight 755 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 755 is a near-IR fluor that is invisible to the naked eye but increases the staining options when using infrared imaging systems. DyLight 755 has spectral properties that are very similar to other near-IR dyes, including Alexa Fluor™ 750. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 755 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 755 NHS Ester:

High performance—DyLight 755 replaces Alexa Fluor 755 for near-infrared staining
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting, or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 755 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 755 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 755 NHS Ester
DyLight™ 755 Antibody Labeling Kit

DyLight™ 350 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 350 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 350 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins.

DyLight 350 is a derivative of aminomethylcoumarine acetate (AMCA) and has a higher fluorescence intensity than Alexa Fluor™ 350 and AMCA in many applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 350 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 350 NHS Ester:

High performance—DyLight 350 shows brighter fluorescence than Alexa Fluor 350 and AMCA
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 350 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 350 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 350 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 350 NHS Ester
DyLight™ 350 Microscale Antibody Labeling Kit

Pierce™ Antibody Biotinylation Kit for IP (Thermo Scientific™)

The Thermo Scientific™ Pierce™ Antibody Biotinylation Kit for IP provides biotinylation reagents designed specifically for the labeling of primary antibodies used in immunoprecipitation applications.

Optimized for IP—reagents and protocols developed specifically to address antibody labeling for immunoprecipitation applications
Easy to use—kit configuration specifically optimized to accommodate 50–200 μg of antibody in a 100 μL reaction; desalting columns are provided to remove excess biotinylation reagent after labeling
Amine reactive—reacts with primary amines (-NH2) of antibodies
Enhanced solubility—pegylation improves water solubility of the biotinylated antibody and prevents aggregation upon storage
Reduced steric hindrance—longer spacer arm (29 angstroms) minimize steric hindrance when binding to avidin molecules

The Pierce Antibody Biotinylation Kit reagents have been optimized and validated to biotin label antibodies for IP and co-IP reactions. Determining the optimal number of biotins to attach to the target molecule is one of the major challenges of biotinylation. For IP and co-IP applications, too many biotins result in reduced affinity for the target antigen, while too few biotins result in antibody leaching upon elution of the target antigen. The biotin labeling procedure in the Pierce Antibody Biotinylation Kit for IP has been developed to address this challenge.

The kit contains sufficient reagents to label 50–200 µg of antibody in 100 µL reaction volumes for eight samples. The NHS-PEG4-biotin labeling reagent contains an amine-reactive N-hydroxysuccinimide ester (NHS) group and a water-soluble PEG4 spacer for optimal labeling and is provided in easy-to-use, single-use microtubes. Both the labeling efficiency of the biotinylation reagent and binding affinity of the labeled antibody have been validated using mouse monoclonal (IgG1, IgG2), rabbit polyconal, and rabbit monoclonal antibodies. Zeba™ Desalting Spin Columns are provided for easy and efficient removal of salts and excess biotin.

Applications:
• IP and co-IP
• IP and co-IP for mass spectrometry applications
• Antibody attachment to streptavidin agarose and magnetic supports

SiteClick™ Qdot™ 605 Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ Qdot® 605 Antibody Labeling Kit. This kit replaces the conventional Qdot® 605 Antibody Conjugation Kit (Q22001MP). Unlike the conventional amine-thiol crosslinker method, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody ensuring that the antigen binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible each time it is performed. Depending upon the label, the resulting SiteClick™ labeled antibody can be used in flow cytometry, fluorescence imaging, or western blot detection.

Important Features of the SiteClick™ Qdot® 605 Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.
• Qdot® 605 labels can be used in confocal or traditional fluoresce microscopy.
• In flow cytometry, Qdot® 605 can be excited by the 488 nm line of the argon-ion laser, or alternatively via excitation at 405 nm. This is true of all Qdot® fluorophores.

Qdot® Fluorophores Are Our Brightest Labels
Antibody conjugates made with Qdot® fluorophores produce fluorescence output that surpasses that of traditional organic dyes. Paired with the correct optical filters, Qdot® nanocrystals are as much as 50 times brighter. Read more about Qdot® nanocrystals or review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

Alexa Fluor™ 555 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with orange fluorescent Alexa Fluor® 555. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 555 Antibody Labeling Kit:
• With an excitation and emission maximum of 555/565 nm, Alexa Fluor® 555 can be efficiently excited using a 543 nm He-Ne laser line and detected under standard TRITC/Cy3® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Zor use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

EZ-Link™ Activated Peroxidase Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific Pierce Activated Peroxidase and Antibody Labeling Kit is designed to prepare and purify HRP-conjugated antibodies with any previously unmodified primary or secondary antibody (IgG).

Features of the Activated Peroxidase and Antibody Labeling Kit:

Activated HRP – glutaraldehyde-activated horseradish peroxidase, ready for conjugation to antibodies and other proteins at sites of primary amines (e.g., lysines)
Permanent conjugation – reacts with primary amines to form covalent amide bonds; no reduction step is necessary to secure the linkage
High activity HRP – enzyme activity is greater than 200 units/mg; lyophilized, activated enzyme is stable for at least 12 months at -20°C
Convenient quantities – each 1 mg-quantity of activated enzyme in the kit is sufficient for reaction with 0.3 mg of IgG to produce about 0.5 mL of conjugate

Activated Peroxidase is HRP enzyme that has been activated with glutaraldehyde to contain reactive groups that will spontaneously conjugate with amines on an antibody (or other protein). Incubation of this Activated Peroxidase with IgG in sodium carbonate buffer (pH 9.5) results in formation of a conjugate where both the enzyme activity of HRP and the antigen-binding activity of IgG are preserved. The Antibody Labeling Kit includes the Activated Peroxidase and a Protein A/G column and buffers to purify the antibody conjugate from excess, unreacted HRP enzyme.

For additional information about glutaraldehyde conjugation, see our review of reductive amination and the discussion of applications that follows.

Alexa Fluor™ 488 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with green fluorescent Alexa Fluor® 488. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 488 Antibody Labeling Kit:
• With an excitation and emission maximum of 494/519 nm, Alexa Fluor® 488 can be efficiently excited using a 488 nm Argon laser line and detected under standard FITC/Cy2® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

DyLight™ 680 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 680 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 680 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins—the amine-reactive DyLight 680 NHS-ester in convenient single-use vials, as well as purification resin and spin columns for the preparation of ready-to-use conjugate..

DyLight 680 produces near-infrared (IR) fluorescence that replaces other near-IR dyes, including Cy5.5™ dye and Alexa Fluor™ 680, and is ideal for multi-color applications.The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 680 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 680 NHS-Ester:

High performance—DyLight 680 fluoresces brighter than Alexa Fluor 680 and Cy5.5 dye
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 680 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 680 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 680 NHS-Ester
DyLight™ 680 Microscale Antibody Labeling Kit

DyLight™ 633 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 633 Microscale Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 633 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG—the amine-reactive DyLight 633 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 633 fluoresces red and has physical properties comparable to other 633 dyes, including Alexa Fluor™ 633. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 633 Amine-Reactive Dye is available as a stand-alone reagent.

Features of DyLight 633 NHS Ester:

High performance—DyLight 633 shows brighter fluorescence than Alexa Fluor 633
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 633 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 633 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 633 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 633 NHS Ester
DyLight™ 633 Antibody Labeling Kit

Pacific Blue™ Antibody Labeling Kit (Invitrogen™)

Molecular Probes™ Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with the violet light-excitable Pacific Orange™ or Pacific Blue™ dyes. This kit is optimized for labeling 100 µg of antibody per reaction. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

View a selection guide for all Antibody Labeling Kits.

View the Fluorophore Selection Guide.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important features of antibody labeling kits:
• Pacific Blue™ has an excitation and emission maximum of 410/455 nm
• Labeled proteins typically ready to use in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better results and workflows with primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Learn more about protein and antibody labeling
We offer a wide selection of Molecular Probes™ antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes™ Handbook.

We'll make a custom antibody conjugate for you
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

Alexa Fluor™ 594 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with red fluorescent Alexa Fluor® 594. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 594 Antibody Labeling Kit:
• With an excitation and emission maximum of 590/617 nm, Alexa Fluor® 594 can be efficiently excited using a 594 nm Kr or He-Ne laser line and detected under standard Texas Red® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Zor use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

DyLight™ 594 Microscale Antibody Labeling Kit (Thermo Scientific™)

Thermo Scientific DyLight 594 Amine-Reactive Dye is an NHS ester-activated derivative of high-performance DyLight 594 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG.

DyLight 594 provides vibrant red fluorescence with better performance than Alexa Fluor™ 594 and Texas Red™ dye for fluorescent applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 594 Amine-Reactive Dye is available as a stand-alone reagent or as part of two antibody labeling kit sizes.

Features of DyLight 594 NHS Ester:

High performance—DyLight 594 shows brighter fluorescence than Alexa Fluor 594 and Texas Red
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 594 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 594 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 594 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 594 NHS Ester
DyLight™ 594 Antibody Labeling Kit

EZ-Link™ NHS-PEG Solid-Phase Biotinylation Kit - 1mL Column (Thermo Scientific™)

Thermo Scientific EZ-Link NHS-PEG Solid Phase Biotinylation Kits provide an on-column approach to amine-targeted antibody biotinylation that provides greater control over the labeling reaction and clean-up process.

Features of the EZ-Link NHS-PEG Solid-Phase Biotinylation Kit:

Ideal for small-scale reactions—0.1 to 1 mg antibody
Fast labeling and purification—the entire procedure takes only about one hour
Easy removal of spent and excess labeling reagent—simply wash away the reaction byproducts—no need for dialysis or gel filtration
No dilution effects—solid-phase method allows initially dilute antibodies to be recovered in a smaller volume after labeling
Optimized protocols—specific protocols for antibody ensure appropriate level of labeling (2 to 5 biotins per antibody molecule), minimizing possibility of inactivation caused by overlabeling
High-performance biotin reagent—NHS-PEG4-Biotin uses efficient, amine-specific NHS-ester chemistry and includes hydrophilic polyethylene glycol (PEG) spacer that stabilizes long-term solubility of labeled antibodies
Eight biotin-labeling experiments per kit—Thermo Scientific No-Weigh Packaging ensures that the biotin reagent is fully active for eight separate experiments

This innovative antibody-labeling system uses nickel-chelated agarose to temporarily immobilize antibody molecules via their histidine-rich Fc regions. Once held in place on the resin, the antibody can be biotinylated at primary amines with the high-quality, solubility-stabilizing NHS-PEG4-Biotin reagent. Excess labeling reagent and byproducts are then washed away before recovering the labeled and purified antibody from the resin using a mild imidazole solution. No gel filtration or dialysis is needed.

EZ-Link Solid-Phase Biotinylation Kits use an innovative strategy for antibody biotinylation that simplifies the process in many respects, making successful biotinylation possible for the novice and expert. The strategy involves immobilizing the antibody to a metal-chelated affinity support and performing the biotinylation in the solid phase.

Antibodies bind readily to metal-chelated supports, such as nickel or cobalt, binding primarily through the histidine-rich Fc region of IgG-class antibodies. This feature allows the derivatization chemistry to be performed easily while the antibody is bound to the support. This strategy facilitates reagent delivery and removal of spent reagent. The resulting modified antibody is then selectively removed from the support by elution with a buffered imidazole solution.

The solid-phase approach to antibody biotinylation provides more control over the reaction. For example: Reagent and antibody ratios and reaction times can be adjusted to achieve the proper degree of biotinylation for the intended application.

The kits contain an aqueous soluble amino group-specific reagent (NHS-PEG4-Biotin) that targets accessible amino (-NH2) groups on the surface of the antibody. The format can be applied at the multi-milligram antibody level in the 1 mL column kit (Part No. 21440) or to low microgram antibody levels for biotinylations using the mini-spin column kit (Part No. 21450).

Related Products
EZ-Link™ NHS-PEG Solid-Phase Biotinylation Kit - Mini-Spin Columns

DyLight™ 488 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 488 Microscale Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 488 for fluorescent labeling of antibodies and other proteins to be used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG.

DyLight 488 has high fluorescence intensity over a broad pH range (pH 4-9) and is more photostable than Cy2™, Alexa™ Fluor 488, FITC and LI-COR™ dyes in many applications. The high water solubility of DyLight Fluors allows a high dye-to-protein ratio to be achieved without causing precipitation of the conjugates. DyLight 488 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of the DyLight 488 NHS Ester:

High performance— DyLight 488 is comparable to Alexa Fluor 488 and brighter than FITC and Cy2
Specific— NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes— standard and microscale sizes are offered to match your experimental needs
Optimized procedure— following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 488 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 488 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

We also offer Standard and Microscale DyLight 488 Antibody Labeling Kits for fast and efficient fluorescent labeling of antibodies for use in fluorescence methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG. Both kit sizes include the Amine-Reactive DyLight 488 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

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DyLight™ 488 NHS Ester
DyLight™ 488 Antibody Labeling Kit

APEX™ Alexa Fluor™ 568 Antibody Labeling Kit (Invitrogen™)

The APEX® Antibody Labeling Kits are our best option for covalently attaching a fluorophore to small amounts of IgG antibody (~10–20 μg). It is ideal for the efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Labeled antibodies are ready for use in imaging or flow cytometry applications in as little as 2.5 hours with very little hands on time.

Important Features of Alexa Fluor® APEX® Antibody Labeling Kits:

• Labeled antibodies typically ready to use in 2.5 hours (~15 minutes hands on time)
• Designed to label 10–20 μg of IgG
• Covalent attachment
• Compatible with contaminating proteins or stabilizers like BSA
• No columns needed; everything you need is supplied for 5 separate labelings
• Choose from Alexa Fluor® 488, 555, 568, 594, and 647 dyes, Oregon Green® 488 dye, Pacific Blue™ dye, and Biotin-XX.


Better Results and Workflows With Primary Labeled Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Contaminating Proteins or Protein Stabilizers Are Not a Problem
Many IgG antibodies are often available only in small quantities and packaged with stabilizing proteins, such as BSA, or other contaminants which can interfere with the amine-reactive labeling reagents. The APEX® Antibody Labeling Kits avoids this by utilizing a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX® antibody labeling tip. Contaminants are simply eluted through the tip, prior to applying the amine-reactive label.

Learn More about Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

Pierce™ NHS-Fluorescein Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific NHS-Fluorescein Antibody Labeling Kit is a multi-component kit containing a high-performance derivative of fluorescein dye, activated for easy and reliable labeling of antibodies, proteins and other molecules for use as fluorescent probes.

Features of the kit:

Easy —convenient kit with NHS-fluorescein to label and purify antibody in about one hour
Amine-specific labeling—the isothiocyanate variety of fluorescein efficiently labels antibodies and other purified proteins at primary amines (lysine side chains)
Optimized kit procedure—following the standard protocol results in antibodies with excellent dye:protein ratios for optimum activity and fluorescence
Single-use fluors—no need to weigh tiny amounts of powder; kits contain single-use vials of reagent
Efficient purification—kits include purification resin and easy-to-use spin columns, ensuring rapid and efficient removal of non-reacted dye and excellent protein recovery

NHS-fluorescein is activated with the N-hydroxy-succinimidyl-ester (NHS ester) functional group. Compared to FITC, the NHS-ester deriviative has greater specificity toward primary amines in the presence of other nucleophiles and results in a more stable linkage following labeling. Pierce Amine-reactive Fluorescein Dyes are mixtures of isomers with reactive groups attached at the 5- and 6-positions of the bottom ring. The properties of these isomers are indistinguishable in terms of excitation and emission spectra, and for protein applications there is no need to isolate a specific isomer.

Properties of NHS-Fluorescein:

• Alternative name: 5/6-FAM SE
• Chemical name: 5/6-carboxyfluorescein succinimidyl ester
• Molecular weight: 473.4
• Excitation source: 488 nm spectral line, argon-ion laser
• Excitation wavelength: 494 nm
• Emission wavelength: 518 nm
• Extinction coefficient: > 70,000 M-1cm-1
• CAS #: 117548-22-8
• Purity: > 90% by HPLC
• Solubility: Soluble in DMF or DMSO
• Reactive groups: NHS ester, reacts with primary amines at pH 7.0 to 9.0

Applications:
• Label antibodies for use as immunofluorescent probes
• Label oligonucleotides for hybridization probes
• Detect proteins in gels and on Western blots

Related Products
NHS-Fluorescein (5/6-carboxyfluorescein succinimidyl ester), mixed isomer
FITC (5/6-fluorescein isothiocyanate), mixed isomer
Pierce™ FITC Antibody Labeling Kit

Alexa Fluor™ 680 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® antibody labeling kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 μg of antibody per reaction with infrared fluorescent Alexa Fluor® 680. Small amounts of other proteins (>40 kDa) can also be labeled with this kit.

The Alexa Fluor® 680 Antibody Labeling Kits contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. The conjugates are ideal for multiple applications, including small animal in vivo imaging, flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

With an excitation and emission maximum of 684/707 nm, Alexa Fluor® 680 can be efficiently excited and detected in most standard small animal in vivo imaging and fluorescent western blot imaging systems.

Important Features of Alexa Fluor® 680 Antibody Labeling Kit:

• Labeled proteins typically ready to use in 90 min (~15 min hands-on time)
• Optimized for small-scale labeling of any protein >40 kDa
• Conjugates purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)

Better Results and Workflows Possible with Labeled Primary Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

DyLight™ 550 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 550 Microscale Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 550 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG.

DyLight 550 provides vibrant orange-to-red fluorescence with better performance than other rhodamine derivatives, including Alexa Fluor™ 555, TRITC, and Cy3™ dye for fluorescent applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 550 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 550 NHS Ester:

High performance—DyLight 550 shows brighter fluorescence than Alexa Fluor 555, TRITC and Cy3 dye
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 550 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 550 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 550 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

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DyLight™ 550 NHS Ester
DyLight™ 550 Antibody Labeling Kit

Alexa Fluor™ 532 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with green-yellow fluorescent Alexa Fluor® 532. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 532 Antibody Labeling Kit:
• With an excitation and emission maximum of 530/554 nm, Alexa Fluor® 532 can be efficiently excited using a 532 nm Nd:YAG laser line and detected under standard Rhodamine 6G filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

DyLight™ 405 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 405 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 405 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins.

DyLight 405 has a vibrant blue fluorescence intensity that replaces Alexa Fluor™ 405, Cascade™ Blue and AMCA in many applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 405 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of the DyLight 405 Amine-Reactive Dye:

High performance— DyLight 405 shows bright fluorescence and replaces Alexa Fluor 405, Cascade Blue and AMCA
Specific— NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes— standard and microscale sizes are offered to match your experimental needs
Optimized procedure— following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 405 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 405 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 405 NHS Ester
DyLight™ 405 Microscale Antibody Labeling Kit

DyLight™ 800 Microscale Antibody Labeling Kit (Thermo Scientific™)

Thermo Scientific DyLight 800 Amine-Reactive Dye is an NHS ester-activated derivative of high-performance DyLight 800 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG—the amine-reactive DyLight 800 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 800 is a near-IR fluor that is invisible to the naked eye but increases the staining options when using infrared imaging systems. DyLight 800 has spectral properties that are very similar to other near-IR dyes, including Alexa Fluor™ 790 and IRDye™ 800. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 800 Amine-Reactive Dye is available as a stand-alone reagent or as part of two antibody labeling kit sizes.

Features of DyLight 800 NHS Ester:

High performance— DyLight 800 replaces Alexa Fluor 800 and IRDye 800 for near-infrared staining
Specific— NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes— standard and microscale sizes are offered to match your experimental needs
Optimized procedure— following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 800 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 800 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

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DyLight™ 800 NHS Ester
DyLight™ 800 Antibody Labeling Kit

SiteClick™ Qdot™ 525 Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ Qdot® 525 Antibody Labeling Kit. This kit replaces the conventional Qdot® 525 Antibody Conjugation Kit (Q22041MP). Unlike the conventional amine-thiol crosslinker method, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody ensuring that the antigen binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible each time it is performed. Depending upon the label, the resulting SiteClick™ labeled antibody can be used in flow cytometry, fluorescence imaging, or western blot detection.

Important Features of the SiteClick™ Qdot® 525 Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.
• Qdot® 525 labels can be used in confocal or traditional fluoresce microscopy.
• In flow cytometry, Qdot® 525 can be excited by the 488 nm line of the argon-ion laser, or alternatively via excitation at 405 nm. This is true of all Qdot® fluorophores.

Qdot® Fluorophores Are Our Brightest Labels
Antibody conjugates made with Qdot® fluorophores produce fluorescence output that surpasses that of traditional organic dyes. Paired with the correct optical filters, Qdot® nanocrystals are as much as 50 times brighter. Read more about Qdot® nanocrystals or review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

SiteClick™ Antibody Azido Modification Kit (Invitrogen™)

Create a label-ready site-specific azido-modified antibody without lengthy and inefficient genetic modification using the SiteClick Antibody Azido Modification Kit. SiteClick labeling uses enzymes to specifically attach an azido moiety to the heavy chains of an IgG antibody, ensuring that the antigen binding domains remain unaltered for binding to the antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. Once azido–modified, a variety of sDIBO alkyne labels are available for attachment to the antibody via Click chemistry (see list below). This provides the flexibility to choose different labels for your antibody depending on your assay.

Features of the SiteClickAntibody Azido Modification Kit:
• Contains everything required to label 100–250 µg of IgG antibody
• Easy-to-follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate

Learn more about SiteClick labeling technology ›

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Click-iT Alexa Fluor 647 sDIBO Alkyne for Antibody Labeling
Click-iT Biotin sDIBO Alkyne for Antibody Labeling
Click-iT Amine sDIBO Alkyne for Antibody Labeling
Click-iT SDP Ester sDIBO Alkyne for Antibody Labeling

Custom SiteClick Antibody Labeling Service
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor dyes, Qdot fluorophores, R-PE, chelates for PET imaging, and many others.

EZ-Link™ Plus Activated Peroxidase Kit (Thermo Scientific™)

Thermo Scientific Pierce Plus Activated Peroxidase is an amine-reactive form of horseradish peroxidase (HRP) that provides coupling efficiencies of greater than 95% with antibodies and other proteins. Each kit contains 5 x 1 mg of lyophilized HRP and sufficient Sodium cyanoborohydride solution, quenching buffer, and buffers to conjugate 5 mg of Immunoglobulin (IgG)

Features of the Thermo Scientific Pierce Plus Activated Peroxidase Kit:

Activated HRP – periodate-treated, aldehyde-activated horseradish peroxidase, ready for conjugation to antibodies and other proteins at sites of primary amines (e.g., lysines)
Permanent conjugation – reacts efficiently (95%) with primary amines to form covalent amide bonds upon treatment with sodium cyanoborohydride (included in kit)
High activity HRP – enzyme activity is 120 to 200 units/mg; lyophilized, activated enzyme is stable for at least 12 months at -20°C
Convenient quantities – each 1 mg-quantity of activated enzyme is sufficient for reaction with 1 mg of IgG to produce about 0.5 mL of conjugate
Customizable – vary the molar ratios, reaction buffer and pH, and other parameters to acheive conjugates with different levels of HRP incorporation and activity

Plus Activated Peroxidase is horseradish peroxidase (HRP) enzyme, whose native carbohydrates (sugars) have been gently oxidized with periodate to produce amine-reactive aldehyde groups. These carbonyls of Plus Activated Peroxidase spontaneously and efficiently crosslink with primary amines on antibody or other proteins. The method is more effective than other amine-reactive chemistries, such as glutaraldehyde coupling, which often causes polymerization and a greater degree of conjugate inactivation. The pre-activated enzyme eliminates the difficulties inherent in preparing and validating activated peroxidase from scratch. The kit provides the enzyme, accessory reagents and protocol to easily produce high-performance conjugates for Western blotting, ELISA and other detection techniques.

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Pierce™ NHS-Rhodamine Antibody Labeling Kit (Thermo Scientific™)

Thermo Scientific NHS-Rhodamine is a high-performance derivative of rhodamine dye, activated for easy and reliable labeling of antibodies, proteins and other molecules for use as fluorescent probes. Use our NHS-Rhodamine Antibody Labeling Kit to label and purify antibodies in about one hour.

Features of NHS-Rhodamine :

Amine-specific labeling—NHS-ester varieties of rhodamine efficiently label antibodies and other purified proteins at primary amines (lysine side chains)
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios for optimum activity and fluorescence
Single-use fluors—no need to weigh tiny amounts powder; kit contains single-use vials of reagent
Efficient purification—kit includes purification resin and easy-to-use spin columns, ensuring rapid and efficient removal of non-reacted dye and excellent protein recovery

NHS Rhodamine is an amine-reactive derivative of rhodamine dye that has wide-ranging application as antibody and other probe labels for use in fluorescence microscopy, flow cytometry and immunofluorescence-based assays such as western blotting and ELISA.

Applications:
• Label antibodies for use as immunofluorescent probes
• Label oligonucleotides for hybridization probes
• Detect proteins in gels and on western blots

Properties of Rhodamine Dyes:
Thermo Scientific Pierce Rhodamine Dyes are mixtures of isomers with reactive groups attached at the 5- and 6-positions of the bottom ring. The properties of these isomers are indistinguishable in terms of excitation and emission spectra, and for protein applications there is no need to isolate a specific isomer.

NHS-Rhodamine is activated with the N-hydroxy-succinimidyl-ester (NHS ester) functional group. Compared to TRITC, the NHS-ester deriviative has greater specificity toward primary amines in the presence of other nucleophiles and results in a more stable linkage following labeling.

Application Data:

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TRITC (5/6-tetramethyl-rhodamine isothiocyanate), mixed isomer

SiteClick™ Qdot™ 625 Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ Qdot® 625 Antibody Labeling Kit. This kit replaces the conventional Qdot® 625 Antibody Conjugation Kit (A10197). Unlike the conventional amine-thiol crosslinker method, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody, ensuring that the antigen-binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible each time it is performed. Depending upon the label, the resulting SiteClick™ -labeled antibody can be used in flow cytometry, fluorescence imaging, or Western blot detection.

Important Features of the SiteClick™ Qdot® 625 Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.
• Qdot® 625 labels can be used in confocal or traditional fluorescence microscopy.
• In flow cytometry, Qdot® 625 can be excited by the 488 nm line of the argon-ion laser, or alternatively via excitation at 405 nm. This is true of all Qdot® fluorophores.

Qdot® Fluorophores are Our Brightest Labels
Antibody conjugates made with Qdot® fluorophores produce fluorescence output that surpasses that of traditional organic dyes. Paired with the correct optical filters, Qdot® nanocrystals are as much as 50 times brighter. Read more about Qdot® nanocrystals or review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

DyLight™ 680 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 680 Microscale Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 680 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG—the amine-reactive DyLight 680 NHS-ester in convenient single-use vials, as well as purification resin and spin columns for the preparation of ready-to-use conjugate..

DyLight 680 produces near-infrared (IR) fluorescence that replaces other near-IR dyes, including Cy5.5™ dye and Alexa Fluor™ 680, and is ideal for multi-color applications.The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 680 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 680 NHS-Ester:

High performance—DyLight 680 fluoresces brighter than Alexa Fluor 680 and Cy5.5 dye
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 680 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 680 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

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Zenon™ pHrodo™ iFL Red Mouse IgG Labeling Reagent (Invitrogen™)

Zenon labeling technology provides a fast, versatile, and reliable method for adding a fluorescent label to an antibody. Only a small amount of starting material is needed, and the method is optimized for efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions.

Combined with pHrodo iFL dye, this technology provides a rapid, scalable, and easy way to determine how well an antibody internalizes into target cells. pHrodo iFL Red dye dramatically increases its fluorescence as the pH of its surroundings becomes more acidic.

• Labeled antibodies typically ready to use in 10 minutes
• Simple, no purification required
• Fast, accurate internalization results—no need for wash steps or quenchers

Preserve primary antibody function and affinities
Reactive dye labeling of primary antibodies can have unpredictable and undesirable outcomes. One of these is reduced binding affinity due to label addition in the binding pocket. The Zenon antibody labeling approach, which is targeted to the Fc tail, avoids this outcome.

Custom antibody conjugates
If the antibody conjugate you need is not available as one of our stocked products, we will prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

APEX™ Alexa Fluor™ 488 Antibody Labeling Kit (Invitrogen™)

The APEX® Antibody Labeling Kits are our best option for covalently attaching a fluorophore to small amounts of IgG antibody (~10–20 μg). It is ideal for the efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Labeled antibodies are ready for use in imaging or flow cytometry applications in as little as 2.5 hours with very little hands on time.

Important Features of Alexa Fluor® APEX® Antibody Labeling Kits:

• Labeled antibodies typically ready to use in 2.5 hours (~15 minutes hands on time)
• Designed to label 10–20 μg of IgG
• Covalent attachment
• Compatible with contaminating proteins or stabilizers like BSA
• No columns needed; everything you need is supplied for 5 separate labelings
• Choose from Alexa Fluor® 488, 555, 568, 594, and 647 dyes, Oregon Green® 488 dye, Pacific Blue™ dye, and Biotin-XX.


Better Results and Workflows With Primary Labeled Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Contaminating Proteins or Protein Stabilizers Are Not a Problem
Many IgG antibodies are often available only in small quantities and packaged with stabilizing proteins, such as BSA, or other contaminants which can interfere with the amine-reactive labeling reagents. The APEX® Antibody Labeling Kits avoids this by utilizing a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX® antibody labeling tip. Contaminants are simply eluted through the tip, prior to applying the amine-reactive label.

Learn More about Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

EZ-Link™ NHS-PEG Solid-Phase Biotinylation Kit - Mini-Spin Columns (Thermo Scientific™)

Thermo Scientific EZ-Link NHS-PEG Solid Phase Biotinylation Kits provide an on-column approach to amine-targeted antibody biotinylation that provides greater control over the labeling reaction and clean-up process.

Features of the EZ-Link NHS-PEG Solid-Phase Biotinylation Kit:

Suitable for larger-scale reactions—1 to 10 mg antibody
Fast labeling and purification—the entire procedure takes only about one hour
Easy removal of spent and excess labeling reagent—simply wash away the reaction byproducts—no need for dialysis or gel filtration
No dilution effects—solid-phase method allows initially dilute antibodies to be recovered in a smaller volume after labeling
Optimized protocols—specific protocols for antibody ensure appropriate level of labeling (2 to 5 biotins per antibody molecule), minimizing possibility of inactivation caused by overlabeling
High-performance biotin reagent—NHS-PEG4-Biotin uses efficient, amine-specific NHS-ester chemistry and includes hydrophilic polyethylene glycol (PEG) spacer that stabilizes long-term solubility of labeled antibodies
Eight biotin-labeling experiments per kit—Thermo Scientific No-Weigh Packaging ensures that the biotin reagent is fully active for eight separate experiments

This innovative antibody-labeling system uses nickel-chelated agarose to temporarily immobilize antibody molecules via their histidine-rich Fc regions. Once held in place on the resin, the antibody can be biotinylated at primary amines with the high-quality, solubility-stabilizing NHS-PEG4-Biotin reagent. Excess labeling reagent and byproducts are then washed away before recovering the labeled and purified antibody from the resin using a mild imidazole solution. No gel filtration or dialysis is needed.

EZ-Link Solid-Phase Biotinylation Kits use an innovative strategy for antibody biotinylation that simplifies the process in many respects, making successful biotinylation possible for the novice and expert. The strategy involves immobilizing the antibody to a metal-chelated affinity support and performing the biotinylation in the solid phase.

Antibodies bind readily to metal-chelated supports, such as nickel or cobalt, binding primarily through the histidine-rich Fc region of IgG-class antibodies. This feature allows the derivatization chemistry to be performed easily while the antibody is bound to the support. This strategy facilitates reagent delivery and removal of spent reagent. The resulting modified antibody is then selectively removed from the support by elution with a buffered imidazole solution.

The solid-phase approach to antibody biotinylation provides more control over the reaction. For example: Reagent and antibody ratios and reaction times can be adjusted to achieve the proper degree of biotinylation for the intended application.

The kits contain an aqueous soluble amino group-specific reagent (NHS-PEG4-Biotin) that targets accessible amino (-NH2) groups on the surface of the antibody. The format can be applied at the multi-milligram antibody level in the 1 mL column kit (Part No. 21440) or to low microgram antibody levels for biotinylations using the mini-spin column kit (Part No. 21450).

Related Products
EZ-Link™ NHS-PEG Solid-Phase Biotinylation Kit - 1 mL Column

DyLight™ 650 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 650 Microscale Antibody Labeling Kit is an NHS ester-activated derivative of high-performance DyLight 650 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG—the amine-reactive DyLight 650 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 650 provides vibrant far-red fluorescence with comparable or improved performance over other dyes, including Alexa Fluor™ 647 and Cy5™ dye, for fluorescent applications.The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 650 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 650 NHS Ester:

High performance—DyLight 650 fluoresces brighter than Alexa Fluor 647 and Cy5
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 650 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 650 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 650 NHS Ester
DyLight™ 650 Antibody Labeling Kit

APEX™ Pacific Blue™ Antibody Labeling Kit (Invitrogen™)

The APEX® Antibody Labeling Kits are our best option for covalently attaching a fluorophore to small amounts of IgG antibody (~10–20 μg). It is ideal for the efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Labeled antibodies are ready for use in imaging or flow cytometry applications in as little as 2.5 hours with very little hands on time.

Important Features of Alexa Fluor® APEX® Antibody Labeling Kits:

• Labeled antibodies typically ready to use in 2.5 hours (~15 minutes hands on time)
• Designed to label 10–20 μg of IgG
• Covalent attachment
• Compatible with contaminating proteins or stabilizers like BSA
• No columns needed; everything you need is supplied for 5 separate labelings
• Choose from Alexa Fluor® 488, 555, 568, 594, and 647 dyes, Oregon Green® 488 dye, Pacific Blue™ dye, and Biotin-XX.


Better Results and Workflows With Primary Labeled Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Contaminating Proteins or Protein Stabilizers Are Not a Problem
Many IgG antibodies are often available only in small quantities and packaged with stabilizing proteins, such as BSA, or other contaminants which can interfere with the amine-reactive labeling reagents. The APEX® Antibody Labeling Kits avoids this by utilizing a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX® antibody labeling tip. Contaminants are simply eluted through the tip, prior to applying the amine-reactive label.

Learn More about Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

SiteClick™ R-PE Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ R-PE Antibody Labeling Kit. Unlike conventional antibody labeling kits, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody ensuring that the antigen binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. Depending upon the label, the resulting SiteClick™ labeled antibody can be used in flow cytometry or any other application.

Important Features of the SiteClick™ R-PE Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.

R-PE (R- Phycoerythrin) as a Bright Label
R-Phycoerythrin (R-PE) is a bright phycobilliprotein extracted from red algae. Its primary absorption (excitation) peak is at 565 nm with secondary peaks at 496 and 545 nm. The broad excitation spectrum and extremely bright fluorescence (emission maxima = ~578 nm) makes it a useful label for multiplexing in immunocytochemisty, especially in flow cytometry and cell sorting( FACS) applications.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

Pacific Orange™ Antibody Labeling Kit (Invitrogen™)

Molecular Probes™ Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with the violet light-excitable Pacific Orange™ or Pacific Blue™ dyes. This kit is optimized for labeling 100 µg of antibody per reaction. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

View a selection guide for all Antibody Labeling Kits.

View the Fluorophore Selection Guide.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important features of antibody labeling kits:
• Pacific Orange™ has an excitation and emission maximum of 400/551 nm
• Labeled proteins typically ready to use in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better results and workflows with primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Learn more about protein and antibody labeling
We offer a wide selection of Molecular Probes™ antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes™ Handbook.

We'll make a custom antibody conjugate for you
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

Alexa Fluor™ 647 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with far red fluorescent Alexa Fluor® 647. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 647 Antibody Labeling Kit:
• With an excitation and emission maximum of 650/668 nm, Alexa Fluor® 647 can be efficiently excited using a 633 or 635 nm Kr or He-Ne laser line and detected under standard APC/Cy5® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Zor use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

Alexa Fluor™ 350 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with blue fluorescent Alexa Fluor® 350. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 350 Antibody Labeling Kit:
• With an excitation and emission maximum of 346/442 nm, Alexa Fluor® 350 can be efficiently excited using a UV laser line and detected under standard DAPI filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

EZ-Link™ Maleimide-PEG Solid-Phase Biotinylation Kit - Mini-Spin Columns (Thermo Scientific™)

The Thermo Scientific EZ-Link Maleimide-PEG Solid-Phase Biotinylation Kit provides an on-column approach to sulfhydryl-targeted antibody biotinylation that provides greater control over the labeling reaction and clean-up process.

Features of the EZ-Link Maleimide-PEG Solid-Phase Biotinylation Kit:

Ideal for small-scale reactions—0.1 to 1 mg antibody
Fast labeling and purification—the entire procedure takes only about two hours
Easy removal of spent and excess labeling reagent—simply wash away the reaction byproducts—no need for dialysis or gel filtration
No dilution effects—solid-phase method allows initially dilute antibodies to be recovered in a smaller volume after labeling
Optimized protocols—specific protocols for antibody ensure gentle disulfide reduction and appropriate level of labeling to minimize the possibility of inactivation
High-performance biotin reagent—Malemide-PEG2-Biotin uses efficient, sulfhydryl-specific maleimide chemistry and includes hydrophilic polyethylene glycol (PEG) spacer that stabilizes long-term solubility of labeled antibodies
Eight biotin-labeling experiments per kit—Thermo Scientific No-Weigh Packaging ensures that the biotin reagent is fully active for eight separate experiments

This innovative antibody-labeling system uses nickel-chelated agarose to temporarily immobilize antibody molecules via their histidine-rich Fc regions. Once held in place on the resin, the antibody can be gently reduced at the hinge-region to produce free sulfhydryls that are then biotinylated with the Maleimide-PEG2-Biotin reagent. Excess labeling reagent and byproducts are then washed away before recovering the labeled and purified antibody from the resin using a mild imidazole solution. No gel filtration or dialysis is needed.

EZ-Link Solid-Phase Biotinylation Kits use an innovative strategy for antibody biotinylation that simplifies the process in many respects, making successful biotinylation possible for the novice and expert. The strategy involves immobilizing the antibody to a metal-chelated affinity support and performing the biotinylation in the solid phase.

Antibodies bind readily to metal-chelated supports, such as nickel or cobalt, binding primarily through the histidine-rich Fc region of IgG-class antibodies. This feature allows the derivatization chemistry to be performed easily while the antibody is bound to the support. This strategy facilitates reagent delivery and removal of spent reagent. The resulting modified antibody is then selectively removed from the support by elution with a buffered imidazole solution.

The solid-phase approach to antibody biotinylation provides more control over the reaction. For example: Reagent and antibody ratios and reaction times can be adjusted to achieve the proper degree of biotinylation for the intended application.

The kits contain an aqueous soluble sulfhydryl group-specific reagent (Maleimide-PEG2-Biotin) that targets accessible sulfhydryl (-SH) groups on the surface of the antibody. The format can be applied to low microgram antibody levels for biotinylations using the mini-spin column kit.

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DyLight™ 633 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 633 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 633 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins—the amine-reactive DyLight 633 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 633 fluoresces red and has physical properties comparable to other 633 dyes, including Alexa Fluor™ 633. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 633 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 633 NHS Ester:

High performance—DyLight 633 shows brighter fluorescence than Alexa Fluor 633
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 633 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 633 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 633 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 633 NHS Ester
DyLight™ 633 Microscale Antibody Labeling Kit

Alexa Fluor™ 568 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with orange-red fluorescent Alexa Fluor® 568. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 568 Antibody Labeling Kit:
• With an excitation and emission maximum of 577/603 nm, Alexa Fluor® 568 can be efficiently excited using a 568 nm Kr laser line and detected under standard Rhodamine Red/Cy3.5® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

DyLight™ 594 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 594 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 594 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins.

DyLight 594 provides vibrant red fluorescence with better performance than Alexa Fluor™ 594 and Texas Red™ dye for fluorescent applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 594 Amine-Reactive Dye is available as a stand-alone reagent or as part of two antibody labeling kit sizes.

Features of DyLight 594 NHS Ester:

High performance—DyLight 594 shows brighter fluorescence than Alexa Fluor 594 and Texas Red
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 594 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 594 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 594 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

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DyLight™ 488 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 488 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 488 for fluorescent labeling of antibodies and other proteins to be used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins.

DyLight 488 has high fluorescence intensity over a broad pH range (pH 4-9) and is more photostable than Cy2™, Alexa™ Fluor 488, FITC and LI-COR™ dyes in many applications. The high water solubility of DyLight Fluors allows a high dye-to-protein ratio to be achieved without causing precipitation of the conjugates. DyLight 488 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of the DyLight 488 NHS Ester:

High performance— DyLight 488 is comparable to Alexa Fluor 488 and brighter than FITC and Cy2
Specific— NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes— standard and microscale sizes are offered to match your experimental needs
Optimized procedure— following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 488 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 488 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

We also offer Standard and Microscale DyLight 488 Antibody Labeling Kits for fast and efficient fluorescent labeling of antibodies for use in fluorescence methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG. Both kit sizes include the Amine-Reactive DyLight 488 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

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Pierce™ FITC Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific FITC Antibody Labeling Kit is a multi-component kit containing a high-performance derivative of fluorescein dye, activated for easy and reliable labeling of antibodies, proteins and other molecules for use as fluorescent probes.

Features of the kit:

Easy —convenient kit with FITC to label and purify antibody in about one hour
Amine-specific labeling—the isothiocyanate variety of fluorescein efficiently labels antibodies and other purified proteins at primary amines (lysine side chains)
Optimized kit procedure—following the standard protocol results in antibodies with excellent dye:protein ratios for optimum activity and fluorescence
Single-use fluors—no need to weigh tiny amounts of powder; kits contain single-use vials of reagent
Efficient purification—kits include purification resin and easy-to-use spin columns, ensuring rapid and efficient removal of non-reacted dye and excellent protein recovery

Properties of FITC:

• Alternative names: 5/6-FITC
• Chemical name: 5(6)-fluorescein isothiocyanate mixed isomer
• Molecular weight: 389.2
• Excitation source: 488 nm spectral line, argon-ion laser
• Excitation wavelength: 494 nm
• Emission wavelength: 518 nm
• Extinction coefficient: > 70,000 M-1cm-1
• CAS #: 27072-45-3
• Purity: > 95% by HPLC
• Solubility: Soluble in aqueous buffers at pH > 6
• Reactive groups: Isothiocyanate, reacts with primary amines at pH 7.0 to 9.0

Applications:
• Label antibodies for use as immunofluorescent probes
• Label oligonucleotides for hybridization probes
• Detect proteins in gels and on Western blots

Amine-reactive Fluorescein Dyes
FITC is the base fluorescein molecule functionalized with an isothiocyanate reactive group (—N=C=S) at one of two hydrogen atoms on the bottom ring of the structure. This derivative is reactive towards primary amine groups on proteins, peptides and other biomolecules. NHS-fluorescein is activated with the N-hydroxy-succinimidyl-ester (NHS ester) functional group. Compared to FITC, the NHS-ester deriviative has greater specificity toward primary amines in the presence of other nucleophiles and results in a more stable linkage following labeling. Pierce Amine-reactive Fluorescein Dyes are mixtures of isomers with reactive groups attached at the 5- and 6-positions of the bottom ring. The properties of these isomers are indistinguishable in terms of excitation and emission spectra, and for protein applications there is no need to isolate a specific isomer.

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NHS-Fluorescein (5/6-carboxyfluorescein succinimidyl ester), mixed isomer
FITC (5/6-fluorescein isothiocyanate), mixed isomer
Pierce™ NHS-Fluorescein Antibody Labeling Kit

DyLight™ 550 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 550 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 550 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins.

DyLight 550 provides vibrant orange-to-red fluorescence with better performance than other rhodamine derivatives, including Alexa Fluor™ 555, TRITC, and Cy3™ dye for fluorescent applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 550 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 550 NHS Ester:

High performance—DyLight 550 shows brighter fluorescence than Alexa Fluor 555, TRITC and Cy3 dye
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 550 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require DyLight 550 Amine-Reactive Dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 550 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 550 NHS Ester
DyLight™ 550 Microscale Antibody Labeling Kit

APEX™ Biotin-XX Antibody Labeling Kit (Invitrogen™)

The APEX® Antibody Labeling Kits are our best option for covalently attaching a fluorophore to small amounts of IgG antibody (~10–20 μg). It is ideal for the efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Labeled antibodies are ready for use in imaging or flow cytometry applications in as little as 2.5 hours with very little hands on time.

Important Features of Alexa Fluor® APEX® Antibody Labeling Kits:

• Labeled antibodies typically ready to use in 2.5 hours (~15 minutes hands on time)
• Designed to label 10–20 μg of IgG
• Covalent attachment
• Compatible with contaminating proteins or stabilizers like BSA
• No columns needed; everything you need is supplied for 5 separate labelings
• Choose from Alexa Fluor® 488, 555, 568, 594, and 647 dyes, Oregon Green® 488 dye, Pacific Blue™ dye, and Biotin-XX.


Better Results and Workflows With Primary Labeled Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Contaminating Proteins or Protein Stabilizers Are Not a Problem
Many IgG antibodies are often available only in small quantities and packaged with stabilizing proteins, such as BSA, or other contaminants which can interfere with the amine-reactive labeling reagents. The APEX® Antibody Labeling Kits avoids this by utilizing a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX® antibody labeling tip. Contaminants are simply eluted through the tip, prior to applying the amine-reactive label.

Learn More about Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

Qdot™ 605 Antibody Conjugation Kit (Invitrogen™)

Qdot® Antibody Conjugation Kits provide a method to conjugate your antibodies quantum dot nanocrystals. The kit contains amine-derivatized, PEG-coated nanocrystals and the amine-thiol crosslinker, SMCC. In addition to antibodies, other thiol-containing molecules can be coupled to these Qdot® nanocrystals using this kit. Primary antibodies labeled using these methods are excellent reagents in flow cytometry, fluorescence imaging, western blots, and more. The kits are available in eight Qdot® nanocrystal colors and supply the reagents needed for two labeling and separation reactions.

Important Features of Qdot® Antibody Conjugation Kits
• Qdot® 605 quantum dot has emission maxima of ~605 nm
• Labeled proteins typically ready to use in 4–5 hours
• Optimized for ~300 μg of whole IgG or polyclonal Fab fragments
• Requires the antibody or protein be purified and reduced prior to labeling

Properties of Qdot® Nanocrystals
The Qdot® nanocrystal is the size of a large macromolecule or protein (~15–20 nm) and represents the brightest class of detection reagents. Qdot® nanocrystals are made from a nanometer-scale crystal of a semiconductor material (CdSe), which is coated with an additional semiconductor shell (ZnS) to improve the optical properties of the material. The Qdot® 705 and Qdot® 800 nanocrystals, which include CdSeTe, are made in a similar fashion. This core-shell material is further coated with a polymer shell that allows the materials to be conjugated to biological molecules and to retain their optical properties.

Qdot® Nanocrystals Are Our Brightest Labels

• Extremely photostable and bright fluorescence (very high fluorescence quantum yield)
• Efficiently excited with single-line excitation sources
• Narrow emission profiles, large Stokes shift

Qdot® nanocrystals are our brightest fluorescent option for labeling, with molar extinction coefficients several orders of magnitude brighter than our brightest organic dyes. Qdot® nanocrystals are an excellent choice for primary antibody based detection or for rare event and even single-molecule studies. By avoiding secondary detection, primary antibody–based approaches compress workflows in addition to allowing matched isotype/species antibodies to be used.

Find Out More About Qdot® Nanocrystals
Read more about Qdot® nanocrystals, review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook, and learn about protocol modifications that may enhance coupling using our Qdot® Antibody Conjugation Kits.

Learn More About Antibody and Protein Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for human or animal therapeutic or diagnostic use.

DyLight™ 800 Antibody Labeling Kit (Thermo Scientific™)

Thermo Scientific DyLight 800 Amine-Reactive Dye is an NHS ester-activated derivative of high-performance DyLight 800 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins—the amine-reactive DyLight 800 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 800 is a near-IR fluor that is invisible to the naked eye but increases the staining options when using infrared imaging systems. DyLight 800 has spectral properties that are very similar to other near-IR dyes, including Alexa Fluor™ 790 and IRDye™ 800. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 800 Amine-Reactive Dye is available as a stand-alone reagent or as part of two antibody labeling kit sizes.

Features of DyLight 800 NHS Ester:

High performance— DyLight 800 replaces Alexa Fluor 800 and IRDye 800 for near-infrared staining
Specific— NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes— standard and microscale sizes are offered to match your experimental needs
Optimized procedure— following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 800 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 800 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 800 NHS Ester
DyLight™ 800 Microscale Antibody Labeling Kit

Click-iT™ pHrodo™ iFL Red sDIBO Alkyne for Antibody Labeling (Invitrogen™)

The Click-iT iFL pHrodo Red sDIBO Alkyne for Antibody Labeling is optimized for easy attachment to azido-modified antibodies using copper-free Click chemistry. This sDIBO label can be used with antibodies that have been modified using the SiteClick Antibody Azido Modification Kit or antibodies that have been engineered to contain azido moieties. These sDIBO alkynes are improved versions of our original DIBO cyclooctynes, yielding conjugates that are less "sticky" and give lower signal background in biological samples.

This modular labeling system gives you the option to choose different fluorescent labels for your antibody and attach another molecule via streptavadin or your own molecule via amine-reactive or amine-containing moieties, depending on your assay.

There are multiple Click-iT sDIBO labels to choose from:
Click-iT Alexa Fluor 488 sDIBO Alkyne for Antibody Labeling
Click-iT Alexa Fluor 555 sDIBO Alkyne for Antibody Labeling
Click-iT Alexa Fluor 647 sDIBO Alkyne for Antibody Labeling
Click-iT Biotin sDIBO Alkyne for Antibody Labeling
Click-iT Amine sDIBO Alkyne for Antibody Labeling
Click-iT SDP Ester sDIBO Alkyne for Antibody Labeling

Learn more about SiteClick labeling technology ›

Custom SiteClick Antibody Labeling Service and sDIBO labels
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor dyes, Qdot fluorophores, R-PE, chelates for PET imaging, and many others.

SiteClick™ Qdot™ 585 Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ Qdot® 585 Antibody Labeling Kit. This kit replaces the conventional Qdot® 585 Antibody Conjugation Kit (Q22011MP). Unlike the conventional amine-thiol crosslinker method, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody ensuring that the antigen binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible each time it is performed. Depending upon the label, the resulting SiteClick™ labeled antibody can be used in flow cytometry, fluorescence imaging, or western blot detection.

Important Features of the SiteClick™ Qdot® 585 Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.
• Qdot® 585 labels can be used in confocal or traditional fluoresce microscopy.
• In flow cytometry, Qdot® 585 can be excited by the 488 nm line of the argon-ion laser, or alternatively via excitation at 405 nm. This is true of all Qdot® fluorophores.

Qdot® Fluorophores Are Our Brightest Labels
Antibody conjugates made with Qdot® fluorophores produce fluorescence output that surpasses that of traditional organic dyes. Paired with the correct optical filters, Qdot® nanocrystals are as much as 50 times brighter. Read more about Qdot® nanocrystals or review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

Alexa Fluor™ 790 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® antibody labeling kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 μg of antibody per reaction with infrared fluorescent Alexa Fluor® 790. Small amounts of other proteins (>40 kDa) can also be labeled with this kit.

The Alexa Fluor® 790 Antibody Labeling Kits contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. The conjugates are ideal for multiple applications, including small animal in vivo imaging, flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

With an excitation and emission maximum of 784/814 nm, Alexa Fluor® 790 can be efficiently excited and detected in most standard small animal in vivo imaging and fluorescent western blot imaging systems.

Important Features of Alexa Fluor® 790 Antibody Labeling Kit:

• Labeled proteins typically ready to use in 90 min (~15 min hands-on time)
• Optimized for small-scale labeling of any protein >40 kDa
• Conjugates purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)

Better Results and Workflows Possible with Labeled Primary Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

Pierce™ Conjugate Purification Kit (Thermo Scientific™)

The Thermo Scientific Pierce Conjugate Purification Kit is a gentle affinity chromatography system for purifying horseradish peroxidase (HRP) or alkaline phosphatase (AP) conjugated antibodies from unreacted enzyme after labeling.

Features of the Conjugate Purification Kit:

Specific for IgG—procedure is designed for removal of HRP or AP enzymes from IgG antibodies; not for use with IgM, IgY, Fab fragments or streptavidin conjugates
Complete kit—includes affinity column, activator and elution buffers, desalting column and storage buffers for HRP and AP conjugates
High capacity—the single-use column-kit is designed for purification of 0.5 to 50 mg of antibody conjugate dissolved in Tris-buffered saline
Improves assays—removing unconjugated enzyme from antibody conjugates often reduces background and improves overal performance of immunoassays

This conjugate purification kit is designed to eliminate excess, unconjugated HRP or Alk-Phos enzyme from labeled antibodies (IgG) after performing antibody-enzyme conjugation reactions. The column of metal-chelate agarose resin binds to IgG-enzyme conjugates but allows non-conjugated enzyme (HRP or AP) to to pass through. A gentle, non-denaturing elution buffer recovers the fully active IgG-HRP or IgG-AP conjugate. The included desalting columns exchange the purified conjugate into any buffer of choice, ready for use in various immunodetection methods.

In this kit procedure, the nickel-chelated agarose binds IgG through a histidine-rich cluster on the Fc region at the junctures of the Cγ2 and Cγ3 domains, which is highly conserved across all mammalian IgGs. Purified IgG from sheep, mouse, goat, rat and rabbit will bind to nickel-chelated resin. Avidin or streptavidin enzyme conjugates cannot be purified by this method because they do not bind to the nickel-chelated agarose. Additionally, this kit cannot be used to purify antibodies from serum because other serum proteins will also bind to the nickel column.

Removing non-conjugated enzyme using this kit can improve assay results. Increase in assay sensitivity, shorter washes and incubation times, and a high signal-to-noise ratio can be more easily achieved when free enzyme is absent from the system. Furthermore, the column concentrates samples, which eases assay optimization when using conjugates in dilute solutions.

Zenon™ pHrodo™ iFL Green Mouse IgG Labeling Reagent (Invitrogen™)

Zenon labeling technology provides a fast, versatile, and reliable method for adding a fluorescent label to an antibody. Only a small amount of starting material is needed, and the method is optimized for efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions.

Combined with pHrodo iFL dye, this technology provides a rapid, scalable, and easy way to determine how well an antibody internalizes into target cells. pHrodo iFL Green dye dramatically increases its fluorescence as the pH of its surroundings becomes more acidic.

• Labeled antibodies typically ready to use in 10 minutes
• Simple, no purification required
• Fast, accurate internalization results—no need for wash steps or quenchers

Preserve primary antibody function and affinities
Reactive dye labeling of primary antibodies can have unpredictable and undesirable outcomes. One of these is reduced binding affinity due to label addition in the binding pocket. The Zenon antibody labeling approach, which is targeted to the Fc tail, avoids this outcome.

Custom antibody conjugates
If the antibody conjugate you need is not available as one of our stocked products, we will prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

DyLight™ 650 Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 650 Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 650 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The standard size kit contains all necessary components to perform three separate labeling reactions using 1 mg of IgG or similar quantities of other proteins—the amine-reactive DyLight 650 NHS-ester in convenient single-use vials as well as purification resin and spin columns for the preparation of ready-to-use conjugate.

DyLight 650 provides vibrant far-red fluorescence with comparable or improved performance over other dyes, including Alexa Fluor™ 647 and Cy5™ dye, for fluorescent applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 650 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of DyLight 650 NHS Ester:

High performance—DyLight 650 fluoresces brighter than Alexa Fluor 647 and Cy5
Specific—NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes—standard and microscale sizes are offered to match your experimental needs
Optimized procedure—following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 650 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 650 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 650 NHS Ester
DyLight™ 650 Microscale Antibody Labeling Kit

APEX™ Alexa Fluor™ 647 Antibody Labeling Kit (Invitrogen™)

The APEX® Antibody Labeling Kits are our best option for covalently attaching a fluorophore to small amounts of IgG antibody (~10–20 μg). It is ideal for the efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Labeled antibodies are ready for use in imaging or flow cytometry applications in as little as 2.5 hours with very little hands on time.

Important Features of Alexa Fluor® APEX® Antibody Labeling Kits:

• Labeled antibodies typically ready to use in 2.5 hours (~15 minutes hands on time)
• Designed to label 10–20 μg of IgG
• Covalent attachment
• Compatible with contaminating proteins or stabilizers like BSA
• No columns needed; everything you need is supplied for 5 separate labelings
• Choose from Alexa Fluor® 488, 555, 568, 594, and 647 dyes, Oregon Green® 488 dye, Pacific Blue™ dye, and Biotin-XX.


Better Results and Workflows With Primary Labeled Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Contaminating Proteins or Protein Stabilizers Are Not a Problem
Many IgG antibodies are often available only in small quantities and packaged with stabilizing proteins, such as BSA, or other contaminants which can interfere with the amine-reactive labeling reagents. The APEX® Antibody Labeling Kits avoids this by utilizing a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX® antibody labeling tip. Contaminants are simply eluted through the tip, prior to applying the amine-reactive label.

Learn More about Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.

SiteClick™ Qdot™ 800 Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ Qdot® 800 Antibody Labeling Kit. This kit replaces the conventional Qdot® 800 Antibody Conjugation Kit (Q22071MP). Unlike the conventional amine-thiol crosslinker method, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody, ensuring that the antigen-binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible each time it is performed. Depending upon the label, the resulting SiteClick™ -labeled antibody can be used in flow cytometry, fluorescence imaging, or Western blot detection.

Important Features of the SiteClick™ Qdot® 800 Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.
• Qdot® 800 labels can be used in confocal or traditional fluorescence microscopy.
• In flow cytometry, Qdot® 800 can be excited by the 488 nm line of the argon-ion laser, or alternatively via excitation at 405 nm. This is true of all Qdot® fluorophores.

Qdot® Fluorophores are Our Brightest Labels
Antibody conjugates made with Qdot® fluorophores produce fluorescence output that surpasses that of traditional organic dyes. Paired with the correct optical filters, Qdot® nanocrystals are as much as 50 times brighter. Read more about Qdot® nanocrystals or review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

Alexa Fluor™ 546 Antibody Labeling Kit (Invitrogen™)

Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with orange fluorescent Alexa Fluor® 546. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 546 Antibody Labeling Kit:
• With an excitation and emission maximum of 554/570 nm, Alexa Fluor®546 can be efficiently excited using a 543 nm He-Ne laser line and detected under standard TRITC/Cy3® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)


Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not for use in diagnostic procedures.

DyLight™ 405 Microscale Antibody Labeling Kit (Thermo Scientific™)

The Thermo Scientific DyLight 405 Microscale Antibody Labeling Kit contains an NHS ester-activated derivative of high-performance DyLight 405 used to fluorescently label antibodies and other proteins that are then used as molecular probes for cellular imaging and other fluorescence detection methods. The microscale kit contains all of the necessary components to perform five separate labeling reactions using 100 µg of IgG.

DyLight 405 has a vibrant blue fluorescence intensity that replaces Alexa Fluor™ 405, Cascade™ Blue and AMCA in many applications. The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates. DyLight 405 Amine-Reactive Dye is also available as a stand-alone reagent.

Features of the DyLight 405 Amine-Reactive Dye:

High performance— DyLight 405 shows bright fluorescence and replaces Alexa Fluor 405, Cascade Blue and AMCA
Specific— NHS ester-activated dye labels proteins and other molecules at primary amines (-NH2)
Convenient kit sizes— standard and microscale sizes are offered to match your experimental needs
Optimized procedure— following the standard protocol results in antibodies with excellent dye:protein ratios and recovery rates for optimum activity and fluorescence labeling

Applications:
• Primary antibody labeling for immunofluorescence microscopy, immunohistochemistry (IHC), Western blotting or ELISA assay
• Target protein labeling for in vitro and in vivo fluorescent detection strategies

DyLight 405 Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to specific amounts of the labeling reagent. This feature allows DyLight 405 Amine-Reactive Dye to be provided in multiple formats with flexible protocols to achieve efficient degrees of labeling.

Related Products
DyLight™ 405 NHS Ester
DyLight™ 405 Antibody Labeling Kit

SiteClick™ Qdot™ 565 Antibody Labeling Kit (Invitrogen™)

Create a perfectly labeled antibody with the SiteClick™ Qdot® 565 Antibody Labeling Kit. This kit replaces the conventional Qdot® 565 Antibody Conjugation Kit (Q22031MP). Unlike the conventional amine-thiol crosslinker method, SiteClick™ labeling specifically attaches the label to the heavy chains of an IgG antibody ensuring that the antigen binding domains remain available for binding to your antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible each time it is performed. Depending upon the label, the resulting SiteClick™ labeled antibody can be used in flow cytometry, fluorescence imaging, or western blot detection.

Important Features of the SiteClick™ Qdot® 565 Antibody Labeling Kit:

• Contains everything required to label 100 µg of IgG antibody
• Easy to follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate.
• Qdot® 565 labels can be used in confocal or traditional fluoresce microscopy.
• In flow cytometry, Qdot® 565 can be excited by the 488 nm line of the argon-ion laser, or alternatively via excitation at 405 nm. This is true of all Qdot® fluorophores.

Qdot® Fluorophores Are Our Brightest Labels
Antibody conjugates made with Qdot® fluorophores produce fluorescence output that surpasses that of traditional organic dyes. Paired with the correct optical filters, Qdot® nanocrystals are as much as 50 times brighter. Read more about Qdot® nanocrystals or review additional product details in Qdot® Nanocrystals—Section 6.6 in the Molecular Probes® Handbook.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits (see Antibody Labeling from A to Z). To learn more about our various kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

Custom SiteClick™ Antibody Labeling Services
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick™ Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick™ antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor® dyes, Qdot® fluorophores, R-PE, and others.

SiteClick™ Biotin Antibody Labeling Kit (Invitrogen™)

Unlike the conventional amine-thiol crosslinker labeling method, the SiteClick Biotin Antibody Labeling Kit specifically attaches the label to the heavy chains of an IgG antibody, ensuring that the antigen-binding domains remain available for binding to the antigen target. This site selectivity is achieved by targeting the carbohydrate domains present on essentially all IgG antibodies regardless of isotype and host species. In addition, no harsh reduction steps are required, and the labeling is consistent and reproducible.

Features of the SiteClickBiotin Antibody Labeling Kit:
• Contains everything required to label 100–250 µg of IgG antibody
• Easy-to-follow step-by-step protocol
• Highly efficient, site-specific, reproducible labeling chemistry results in high quality antibody conjugate

Learn more about SiteClick labeling technology ›
Learn more about streptavidin detection ›
Learn more about protein and antibody labeling › (We offer a wide selection of antibody and protein labeling kits.)

Custom SiteClick Antibody Labeling Service
If you have an antibody that is considered "difficult to label" or has lost activity after labeling using a conventional method, please contact our custom service representatives to determine whether the SiteClick Antibody Labeling Service would be right for your antibody. We offer complete custom SiteClick antibody labeling services with the option of multiple detection molecules including biotin, Alexa Fluor dyes, Qdot fluorophores, R-PE, chelates for PET imaging, and many others.

APEX™ Alexa Fluor™ 594 Antibody Labeling Kit (Invitrogen™)

The APEX® Antibody Labeling Kits are our best option for covalently attaching a fluorophore to small amounts of IgG antibody (~10–20 μg). It is ideal for the efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Labeled antibodies are ready for use in imaging or flow cytometry applications in as little as 2.5 hours with very little hands on time.

Important Features of Alexa Fluor® APEX® Antibody Labeling Kits:

• Labeled antibodies typically ready to use in 2.5 hours (~15 minutes hands on time)
• Designed to label 10–20 μg of IgG
• Covalent attachment
• Compatible with contaminating proteins or stabilizers like BSA
• No columns needed; everything you need is supplied for 5 separate labelings
• Choose from Alexa Fluor® 488, 555, 568, 594, and 647 dyes, Oregon Green® 488 dye, Pacific Blue™ dye, and Biotin-XX.


Better Results and Workflows With Primary Labeled Antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Contaminating Proteins or Protein Stabilizers Are Not a Problem
Many IgG antibodies are often available only in small quantities and packaged with stabilizing proteins, such as BSA, or other contaminants which can interfere with the amine-reactive labeling reagents. The APEX® Antibody Labeling Kits avoids this by utilizing a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX® antibody labeling tip. Contaminants are simply eluted through the tip, prior to applying the amine-reactive label.

Learn More about Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We’ll Make a Custom Antibody Conjugate for You
If you can’t find what you’re looking for in our stocked list, we’ll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

For Research Use Only. Not intended for animal or human therapeutic or diagnostic use.