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Zenon™ Tricolor Rabbit IgG Labeling Kit #2 (for Blue, Green and Red Fluorescence Imaging) (Invitrogen™)

Zenon® labeling technology provides a fast, versatile, and reliable method for adding a fluorescent label to an antibody. You need only a small amount of starting material, and the method is optimized for efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Antibody conjugates formed using Zenon® technology may be used in any protocol where a directly labeled primary antibody is suitable, including flow cytometry, imaging, and high-throughput applications. This exclusive Molecular Probes® Zenon® labeling technology greatly simplifies the use of multiple mouse-derived antibodies in the same staining protocol. Zenon® Tricolor Labeling Kits contain sufficient materials for 10 labeling reactions of each of three different fluorescent colors.

Important Features of Zenon® Labeling Technology:

• Labeled antibodies typically ready to use in 10 minutes
• Requires only 1–20 μg primary antibody
• Simple, no purification required
• Flexible–over 24 fluorophores plus biotin, HRP, alkaline phosphatase, and TSA to choose from
• Multiplex with other mouse monoclonal antibodies simultaneously


Save Time and Antibody
Each kit comes with affinity-purified monovalent Fab fragment of a goat anti-Fc antibody (or, in the case of the Zenon® Goat IgG Labeling Kits, a rabbit anti-Fc antibody) that has been conjugated to one of our premier Alexa Fluor® dyes or to Pacific Blue™, Pacific Orange™, fluorescein, or Texas Red®-X dyes, biotin R-phycoerythrin (R-PE), allophycocyanin (APC), HRP, or alkaline phosphatase.

Formation of the Fab–antibody complex with the Zenon® Antibody Labeling Kits is extremely fast (5 min for complex, 5 min for blocking step). And Zenon® labeling is a reliable and reproducible method, even with as low 0.4 μg in 2 μL of primary antibody. There is minimal waste of expensive or difficult-to-obtain antibodies when using the Zenon® Antibody Labeling Kits.

Preserve Primary Antibody Function and Affinities
Reactive dye labeling of primary antibodies can have unpredictable and undesirable outcomes. Among these are reduced binding affinities by label addition in the binding pocket. Zenon® antibody labeling approach, targeted to the Fc tail, avoids this concern.

Moreover the Zenon® dye- and enzyme-labeled Fab fragments have been affinity purified during their preparation to help ensure their high affinity and selectivity for the Fc portion of the corresponding primary antibody. The procedure for chemical labeling of the Fab fragments protects the Fc-binding site, resulting in more active labeling reagents.

Many Fluorophore and Enzyme Labels Available
Zenon® immunolabeling technology makes it very easy to change fluorescent color combinations or detection methodologies by simply using a different dye- or enzyme-labeled Fab fragment from our extensive selection of over 100 Zenon® Antibody Labeling Kits. If larger quantities or covalent attachment of the label is desired, see Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices.

Zenon® Technology Simplifies the Use of Multiple Antibodies of the Same Isotype in the Same Protocol
The stability of the Zenon® complex is sufficient to allow sequential (or simultaneous) labeling of different targets in cells and tissues with multiple antibody complexes. Subsequent to staining, an aldehyde-based fixation step can permanently block the transfer of Zenon® labels between different primary antibodies and will preserve the staining pattern.

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.

Related Links:

Zenon® Labeling Technology
Zenon® Technology: Versatile Reagents for Immunolabeling—Section 7.3

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

GlycanAssure™ HyPerformance APTS Kit with CE Module (Applied Biosystems™)

The GlycanAssure HyPerformance APTS Kit is an N‑glycan rapid‑release, labeling, and cleanup kit that offers an N-glycan sample prep workflow for high-throughput glycan characterization applications within biopharma. Combined with the Applied Biosystems 3500xL Genetic Analyzer or Thermo Scientific Vanquish UHPLC system, the GlycanAssure HyPerformance APTS Kit offers an end-to-end N-glycan analysis solution, from clone selection to lot release. This version of the kit contains a CE module with additional chemistries needed for CE analysis.

Key features include:
• Easy N-glycan sample prep workflow for both LC & CE analysis platforms
• Superior data quality with unparalleled robustness
• Proprietary denaturant delivering complete deglycosylation of glycoproteins
• Preservation of sialylation offering accurate quantitation of sialylated glycans
• High-throughput end-to-end N-glycan analysis significantly reducing time to results

Workflow
Glycosylation is one of the key critical quality attributes of glycoprotein (mAb)-based biotherapeutics. Current glycan analysis methods consist of labor-intensive sample preparation that involve the use of toxic reagents, time-consuming vacuum centrifugation steps, and multiple pipetting steps.

The GlycanAssure HyPerformance APTS workflow overcomes these limitations. It delivers complete deglocosylation using a proprietary denaturant and superior preservation of sialylation, an important quality attribute of glycoproteins. Accurate quantitation of sialylated glycans is critical in biosimilar development. Most common sample prep methods cause de-sialylation of the glycans, leading to inaccurate quantitation. In addition, LC based separation techniques poorly quantitate highly sialylated glycans because they elute at the end of the LC profile. The GlycanAssure HyPerformance kit offers excellent preservation of sialylated glycans and allows analysis on a CE instrument where highly sialylated glycans migrate at the beginning of the electropherogram, enabling accurate quantitation.

The released, labelled glycans can be analyzed with either the Applied BioSystems 3500xL Genetic Analyzer for Protein Quality Analysis for high throughput applications or Thermo Scientific Vanquish Flex UHPLC System for lower throughput applications, for an end-to-end glycan analysis solution from Thermo Fisher Scientific.

Kit description
The GlycanAssure HyPerformance APTS Kit is part of the GlycanAssure Glycan Analysis and Quantitation System and contains all reagents and buffers needed to analyze and quantitate N-glycans from glycoprotein samples. APTS is a traditional dye used for glycan labeling and the labeled glycans can be analyzed using capillary electrophoresis (CE) or liquid chromatography (LC) systems. The GlycanAssure sample preparation workflow is a streamlined, automatable method for the processing and analysis of 96 glycoprotein samples in ~5 hrs.

The GlycanAssure HyPerformance APTS kit contains:
• GlycanAssure core reagents
• GlycanAssure beads
• GlycanAssure APTS labeling reagents
• GlycanAssure kit user guide

Alexa Fluor™ 633 NHS Ester (Succinimidyl Ester) (Invitrogen™)

Alexa Fluor® 633 is a bright and photostable far-red dye with excitation ideally suited to the 633 nm laser line. Used for stable signal generation in imaging and flow cytometry, Alexa Fluor® 633 dye is water soluble and pH-insensitive from pH 4 to pH 10. Fluorescence of this long-wavelength Alexa Fluor® dye is not visible to the human eye but is readily detected by most imaging systems. In addition to reactive dye formulations, we offer Alexa Fluor® 633 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection.The NHS ester (or succinimidyl ester) of Alexa Fluor® 633 is the most popular tool for conjugating this dye to a protein or antibody. NHS esters can be used to label to the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting Alexa Fluor® conjugate will exhibit brighter fluorescence and greater photostability than the conjugates of other spectrally similar fluorophores.

Detailed information about this AlexaFluor® NHS ester:

Fluorophore label: Alexa Fluor® 633 dye
Reactive group: NHS ester
Reactivity: Primary amines on proteins and ligands, amine-modified oligonucleotides
Ex/Em of the conjugate: 621/639 nm
Extinction coefficient: 159,000 cm-1M-1
Spectrally similar dyes: Cy5®
Molecular weight: ~1200

Typical Conjugation Reaction
You can conjugate amine-reactive reagents with virtually any protein or peptide (the provided protocol is optimized for IgG antibodies). You can scale the reaction for any amount of protein, but the concentration of the protein should be at least 2 mg/mL for optimal results. We recommend trying three different degrees of labeling, using three different molar ratios of the reactive reagent to protein.

The Alexa Fluor® NHS ester is typically dissolved in high-quality anhydrous dimethylformamide (DMF) or dimethylsulfoxide (DMSO) (D12345), and the reaction is carried out in 0.1–0.2 M sodium bicarbonate buffer, pH 8.3, at room temperature for 1 hour. Because the pKa of the terminal amine is lower than that of the lysine epsilon-amino group, you may achieve more selective labeling of the amine terminus using a buffer closer to neutral pH.

Conjugate Purification
Labeled antibodies are typically separated from free Alexa Fluor® dye using a gel filtration column, such as Sephadex™ G-25, BioGel® P-30, or equivalent. For much larger or smaller proteins, select a gel filtration media with an appropriate molecular weight cut-off or purify by dialysis. We offer several purification kits optimized for different quantities of antibody conjugate:
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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.

Zenon™ Alexa Fluor™ 488 Human IgG Labeling Kit (Invitrogen™)

Zenon® labeling technology provides a fast, versatile, and reliable method for adding a fluorescent label to an antibody. You need only a small amount of starting material, and the method is optimized for efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Antibody conjugates formed using Zenon® technology may be used in any protocol where a directly labeled primary antibody is suitable, including flow cytometry, imaging, and high-throughput applications. This exclusive Molecular Probes® Zenon® labeling technology greatly simplifies the use of multiple mouse-derived antibodies in the same staining protocol.

Important Features of Zenon® Labeling Technology:

• Labeled antibodies typically ready to use in 10 minutes
• Requires only 1–20 μg primary antibody
• Simple, no purification required
• Flexible–over 24 fluorophores plus biotin, HRP, alkaline phosphatase, and TSA to choose from
• Multiplex with other mouse monoclonal antibodies simultaneously


Save Time and Antibody
Each kit comes with affinity-purified monovalent Fab fragment of a goat anti-Fc antibody (or, in the case of the Zenon® Goat IgG Labeling Kits, a rabbit anti-Fc antibody) that has been conjugated to one of our premier Alexa Fluor® dyes or to Pacific Blue™, Pacific Orange™, fluorescein, or Texas Red®-X dyes, biotin R-phycoerythrin (R-PE), allophycocyanin (APC), HRP, or alkaline phosphatase.

Formation of the Fab–antibody complex with the Zenon® Antibody Labeling Kits is extremely fast (5 min for complex, 5 min for blocking step). And Zenon® labeling is a reliable and reproducible method, even with as low 0.4 μg in 2 μL of primary antibody. There is minimal waste of expensive or difficult-to-obtain antibodies when using the Zenon® Antibody Labeling Kits.

Preserve Primary Antibody Function and Affinities
Reactive dye labeling of primary antibodies can have unpredictable and undesirable outcomes. Among these are reduced binding affinities by label addition in the binding pocket. Zenon® antibody labeling approach, targeted to the Fc tail, avoids this concern.

Moreover the Zenon® dye- and enzyme-labeled Fab fragments have been affinity purified during their preparation to help ensure their high affinity and selectivity for the Fc portion of the corresponding primary antibody. The procedure for chemical labeling of the Fab fragments protects the Fc-binding site, resulting in more active labeling reagents.

Many Fluorophore and Enzyme Labels Available
Zenon® immunolabeling technology makes it very easy to change fluorescent color combinations or detection methodologies by simply using a different dye- or enzyme-labeled Fab fragment from our extensive selection of over 100 Zenon® Antibody Labeling Kits. If larger quantities or covalent attachment of the label is desired, see Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices.

Zenon® Technology Simplifies the Use of Multiple Antibodies of the Same Isotype in the Same Protocol
The stability of the Zenon® complex is sufficient to allow sequential (or simultaneous) labeling of different targets in cells and tissues with multiple antibody complexes. Subsequent to staining, an aldehyde-based fixation step can permanently block the transfer of Zenon® labels between different primary antibodies and will preserve the staining pattern.

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.

Related Links:

Zenon® Labeling Technology
Zenon® Technology: Versatile Reagents for Immunolabeling—Section 7.3

Alexa Fluor™ 680 NHS Ester (Succinimidyl Ester) (Invitrogen™)

Alexa Fluor® 680 is a bright and photostable near-IR dye that is spectrally similar to the Cy5.5 dye. Used for stable signal generation in imaging and flow cytometry, Alexa Fluor® 680 dye is water soluble and pH-insensitive from pH 4 to pH 10. Fluorescence of this long-wavelength Alexa Fluor® dye is not visible to the human eye but is readily detected by most imaging systems. In addition to reactive dye formulations, we offer Alexa Fluor® 680 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection (learn more).

The NHS ester (or succinimidyl ester) of Alexa Fluor® 680 is the most popular tool for conjugating this dye to a protein or antibody. NHS esters can be used to label to the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting Alexa Fluor® conjugate will exhibit brighter fluorescence and greater photostability than the conjugates of other spectrally similar fluorophores.

Detailed information about this AlexaFluor® NHS ester:

Fluorophore label: Alexa Fluor® 680 dye
Reactive group: NHS ester
Reactivity: Primary amines on proteins and ligands, amine-modified oligonucleotides
Ex/Em of the conjugate: 684/707 nm
Extinction coefficient: 183,000 cm-1M-1
Spectrally similar dyes: Cy5.5

Typical Conjugation Reaction
You can conjugate amine-reactive reagents with virtually any protein or peptide (the provided protocol is optimized for IgG antibodies). You can scale the reaction for any amount of protein, but the concentration of the protein should be at least 2 mg/mL for optimal results. We recommend trying three different degrees of labeling, using three different molar ratios of the reactive reagent to protein.

The Alexa Fluor® NHS ester is typically dissolved in high-quality anhydrous dimethylformamide (DMF) or dimethylsulfoxide (DMSO) (D12345), and the reaction is carried out in 0.1–0.2 M sodium bicarbonate buffer, pH 8.3, at room temperature for 1 hour. Because the pKa of the terminal amine is lower than that of the lysine epsilon-amino group, you may achieve more selective labeling of the amine terminus using a buffer closer to neutral pH.

Conjugate Purification
Labeled antibodies are typically separated from free Alexa Fluor® dye using a gel filtration column, such as Sephadex™ G-25, BioGel® P-30, or equivalent. For much larger or smaller proteins, select a gel filtration media with an appropriate molecular weight cut-off or purify by dialysis. We offer several purification kits optimized for different quantities of antibody conjugate:
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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.

Fluorescein-5-Isothiocyanate (FITC 'Isomer I') (Invitrogen™)

Searching for superior alternatives to fluorescein? Our Alexa Fluor Dye Series offers everything you're looking for and more.

BODIPY™ TR Cadaverine (5-(((4-(4,4-Difluoro-5-(2-Thienyl)-4-Bora-3a,4a-Diaza-s-Indacene-3-yl)phenoxy)acetyl)amino)pentylamine, Hydrochloride) (Invitrogen™)

The amine-containing BODIPY® TR cadaverine can be reversibly coupled to aldehydes and ketones to form a Schiff base - which can be reduced to a generate stable amine derivative by sodium borohydride (NaBH4) or sodium cyanoborohydride (NaCNH3). Carboxylic acids of proteins and other water-soluble biopolymers can be coupled to this molecule in aqueous solution using water-soluble carbodiimides such as EDAC (E2247). The electronically neutral BODIPY® TR dye is spectrally similar to the red fluorescent Texas Red®® dye.

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.

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

QSY™ 21 Carboxylic Acid, Succinimidyl Ester (Invitrogen™)

The amine-reactive quencher, QSY® 21 succinimidyl ester has a broad and intense absorption (~661 nm maxima) but no fluorescence making it useful as an acceptor in fluorescence resonance energy transfer (FRET) applications.

Alexa Fluor™ 488 5-SDP Ester (Alexa Fluor™ 488 Sulfodichlorophenol Ester) (Invitrogen™)

The SDP (sulfodicholorphenol) ester is currently the most hydrolytically stable amine-reactive moiety available from Invitrogen. Conjugates produced with the Alexa Fluor® 488 5-SDP ester produce the same strong amide bond between the dye and the compound of interest as succinimidyl (SE or NHS) and tetrafluorophenyl (TFP) esters, but with the improved stability in water and buffers, the SDP ester can potentially offer increased control and consistency in these reactions compared to the NHS and TFP esters.

Zenon™ pHrodo™ iFL Green Human 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.

Click-iT™ Alexa Fluor™ 555 sDIBO Alkyne for Antibody Labeling (Invitrogen™)

The Click-iT Alexa Fluor 555 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.

pHrodo™ iFL Green STP Ester (amine-reactive) (Invitrogen™)

The amine-reactive pH-sensitive pHrodo iFL Green STP Ester dye is an improved version of pHrodo Green dye optimized for the creation of bioconjugates to be used in the study of antibody internalization, endocytosis, and phagocytosis. pHrodo iFL Green dye dramatically increases fluorescence as the pH of its surroundings become more acidic. It is more soluble than the original pHrodo Green dye, making it more useful for the labeling of antibodies that may otherwise precipitate out of solution during conjugation.

• Use pH-sensitive pHrodo iFL Green STP Ester to make pH-sensitive bioconjugates of your choice
• Get faster, more accurate results than with any other endocytosis or phagocytosis assay—no need for wash steps or quenchers
• Multiplex with red fluorescent markers such as RFP, pHrodo iFL Red STP, and many others

The increase in fluorescence of pHrodo iFL Green dye as the pH changes from basic to acidic correlates with the acidification of intracellular vesicles, making it a valuable tool for the study of endocytosis or phagocytosis and their regulation by environmental factors, drugs, or pathogens. The spectral properties of pHrodo iFL Green dye make it useful for multi-color experiments. pHrodo iFL Green dye can be detected using most standard green-fluorescent filter sets and has been validated for use in a variety of applications, including flow cytometry, fluorescent microscopy, and high content screening (HCS). The lack of fluorescence of pHrodo iFL Green dye in a typical extracellular environment eliminates the need for wash steps or quencher dyes in the experimental workflow.

pHrodo iFL Green STP Ester is an amine-reactive dye that can be used to make pHrodo iFL Green STP bioconjugates in aqueous buffer. The STP ester will react with primary amines on a protein, cell, or virus to create a stable conjugate that can be used in live cell assays or stored for later use.

LanthaScreen™ Thiol Reactive Tb Chelate

As part of the LanthaScreen® TR-FRET toolbox of assay reagents, LanthaScreen® Thiol Reactive Tb Chelate labeling reagent is available for assay development. The thiol-reactive maleimide group can be conjugated to virtually any peptide or protein that contains one or more accessible thiol moieties, such as the thiol group found on a cysteine residue. Energy transfer from the terbium donor to a suitable acceptor such as fluorescein is readily detected by monitoring an increase in acceptor fluorescence intensity. See the user guide for an application-based protocol for cysteine-containing peptides or proteins.

Fluorescein-5-Maleimide (Invitrogen™)

Searching for superior alternatives to fluorescein? Our Alexa Fluor Dye Series offers everything you're looking for and more.

Alexa Fluor™ 647 NHS Ester (Succinimidyl Ester) (Invitrogen™)

Alexa Fluor® 647 is a bright and photostable far-red dye with excitation ideally suited to the 633 nm laser line. Used for stable signal generation in imaging and flow cytometry, Alexa Fluor® 647 dye is water soluble and pH-insensitive from pH 4 to pH 10. Fluorescence of this long-wavelength Alexa Fluor® dye is not visible to the human eye but is readily detected by most imaging systems. In addition to reactive dye formulations, we offer Alexa Fluor® 647 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection (learn more).

The NHS ester (or succinimidyl ester) of Alexa Fluor® 647 is the most popular tool for conjugating this dye to a protein or antibody. NHS esters can be used to label to the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting Alexa Fluor® conjugate will exhibit brighter fluorescence and greater photostability than the conjugates of other spectrally similar fluorophores.

Detailed information about this AlexaFluor® NHS ester:

Fluorophore label: Alexa Fluor® 647 dye
Reactive group: NHS ester
Reactivity: Primary amines on proteins and ligands, amine-modified oligonucleotides
Ex/Em of the conjugate: 651/672 nm
Extinction coefficient: 270,000 cm-1M-1
Spectrally similar dyes: Cy5®
Molecular weight: ~1250

Typical Conjugation Reaction
You can conjugate amine-reactive reagents with virtually any protein or peptide (the provided protocol is optimized for IgG antibodies). You can scale the reaction for any amount of protein, but the concentration of the protein should be at least 2 mg/mL for optimal results. We recommend trying three different degrees of labeling, using three different molar ratios of the reactive reagent to protein.

The Alexa Fluor® NHS ester is typically dissolved in high-quality anhydrous dimethylformamide (DMF) or dimethylsulfoxide (DMSO) (D12345), and the reaction is carried out in 0.1–0.2 M sodium bicarbonate buffer, pH 8.3, at room temperature for 1 hour. Because the pKa of the terminal amine is lower than that of the lysine epsilon-amino group, you may achieve more selective labeling of the amine terminus using a buffer closer to neutral pH.

Conjugate Purification
Labeled antibodies are typically separated from free Alexa Fluor® dye using a gel filtration column, such as Sephadex™ G-25, BioGel® P-30, or equivalent. For much larger or smaller proteins, select a gel filtration media with an appropriate molecular weight cut-off or purify by dialysis. We offer several purification kits optimized for different quantities of antibody conjugate:
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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™ 488 Hydrazide (Invitrogen™)

Alexa Fluor® 488 Hydrazide is useful as a cell tracer and as a reactive dye for labeling aldehydes or ketones in polysaccharides or glycoproteins. Alexa Fluor® 488 is a bright, green fluorescent dye with excitation ideally suited to the 488 nn laser line. Used for stable signal generation in imaging and flow cytometry, Alexa Fluor® 488 dye is water soluble and pH-insensitive from pH 4 to pH 10. In addition to reactive dye formulations, we offer Alexa Fluor® 488 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection (learn more).

Detailed information about this AlexaFluor® hydrazide:

• Fluorophore label : Alexa Fluor® 488 dye
• Reactive group: hydrazide
• Reactivity: Aldehydes or keytones in polysaccharides or glycoproteins
• Ex/Em of the conjugate: 493/517 nm
• Extinction coefficient: 71,000 cm-1M-1
• Spectrally similar dyes: FITC, GFP
• Molecular weight: 570.48

Cell Tracking and Tracing Applications
Alexa Fluor® hydrazides and hydroxlamines are useful as low molecular weight, membrane-impermeant, aldehyde-fixable cell tracers, exhibiting brighter fluorescence and greater photostability than cell tracers derived from other spectrally similar fluorophores. They are easily loaded into cells by microinjection, infusion from patch pipette, or uptake induced by our Influx™ Pinocytic Cell-Loading Reagent. Learn more about cell tracking and tracing.

Glycoprotein and Polysaccharide Labeling Applications
The Alexa Fluor® hydrazides and hydroxlamines are reactive molecules that can be used to add a fluorescent label to biomolecules containing aldehydes or ketones. Aldehydes and ketones can be introduced into polysaccharides and glycoproteins by periodate-mediated oxidation of vicinal diols. Galactose oxidase can also be used to oxidize terminal galactose residues of glycoproteins to aldehydes.

Hydrazide vs Hydroxylamine
Hydrazine derivatives react with ketones and aldehydes to yield relatively stable hydrazones. Hydroxylamine derivatives (aminooxy compounds) react with aldehydes and ketones to yield oximes. Oximes are superior to hydrazones with respect to hydrolytic stability. Both hydrazones and oximes can be reduced with sodium borohydride (NaBH4) to further increase the stability of the linkage.

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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.

Related Products
DMSO (dimethylsulfoxide) (D12345)
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

Alexa Fluor™ 514 NHS Ester (Succinimidyl Ester) (Invitrogen™)

Alexa Fluor® 514 is a bright, green-fluorescent dye. Used for stable signal generation in imaging and flow cytometry, Alexa Fluor® 514 dye is water soluble and pH-insensitive from pH 4 to pH 10. In addition to reactive dye formulations, we offer Alexa Fluor® 514 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection.

The NHS ester (or succinimidyl ester) of Alexa Fluor® 514 is the most popular tool for conjugating this dye to a protein or antibody. NHS esters can be used to label to the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting Alexa Fluor® conjugate will exhibit brighter fluorescence and greater photostability than the conjugates of other spectrally similar fluorophores.

Detailed information about this AlexaFluor® NHS ester:

Fluorophore label: Alexa Fluor® 514 dye
Reactive group: NHS ester
Reactivity: Primary amines on proteins and ligands, amine-modified oligonucleotides
Ex/Em of the conjugate: 517/542 nm
Extinction coefficient: 80,000 cm-1M-2

Typical Conjugation Reaction
You can conjugate amine-reactive reagents with virtually any protein or peptide (the provided protocol is optimized for IgG antibodies). You can scale the reaction for any amount of protein, but the concentration of the protein should be at least 2 mg/mL for optimal results. We recommend trying three different degrees of labeling, using three different molar ratios of the reactive reagent to protein.

The Alexa Fluor® NHS ester is typically dissolved in high-quality anhydrous dimethylformamide (DMF) or dimethylsulfoxide (DMSO) (D12345), and the reaction is carried out in 0.1–0.2 M sodium bicarbonate buffer, pH 8.3, at room temperature for 1 hour. Because the pKa of the terminal amine is lower than that of the lysine epsilon-amino group, you may achieve more selective labeling of the amine terminus using a buffer closer to neutral pH.

Conjugate Purification
Labeled antibodies are typically separated from free Alexa Fluor® dye using a gel filtration column, such as Sephadex™ G-25, BioGel® P-30, or equivalent. For much larger or smaller proteins, select a gel filtration media with an appropriate molecular weight cut-off or purify by dialysis. We offer several purification kits optimized for different quantities of antibody conjugate:
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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.

Zenon™ Alexa Fluor™ 594 Human IgG Labeling Kit (Invitrogen™)

Zenon® labeling technology provides a fast, versatile, and reliable method for adding a fluorescent label to an antibody. You need only a small amount of starting material, and the method is optimized for efficient labeling of antibodies in serum, ascites fluid, or hybridoma suspensions. Antibody conjugates formed using Zenon® technology may be used in any protocol where a directly labeled primary antibody is suitable, including flow cytometry, imaging, and high-throughput applications. This exclusive Molecular Probes® Zenon® labeling technology greatly simplifies the use of multiple mouse-derived antibodies in the same staining protocol.

Important Features of Zenon® Labeling Technology:

• Labeled antibodies typically ready to use in 10 minutes
• Requires only 1–20 μg primary antibody
• Simple, no purification required
• Flexible–over 24 fluorophores plus biotin, HRP, alkaline phosphatase, and TSA to choose from
• Multiplex with other mouse monoclonal antibodies simultaneously


Save Time and Antibody
Each kit comes with affinity-purified monovalent Fab fragment of a goat anti-Fc antibody (or, in the case of the Zenon® Goat IgG Labeling Kits, a rabbit anti-Fc antibody) that has been conjugated to one of our premier Alexa Fluor® dyes or to Pacific Blue™, Pacific Orange™, fluorescein, or Texas Red®-X dyes, biotin R-phycoerythrin (R-PE), allophycocyanin (APC), HRP, or alkaline phosphatase.

Formation of the Fab–antibody complex with the Zenon® Antibody Labeling Kits is extremely fast (5 min for complex, 5 min for blocking step). And Zenon® labeling is a reliable and reproducible method, even with as low 0.4 μg in 2 μL of primary antibody. There is minimal waste of expensive or difficult-to-obtain antibodies when using the Zenon® Antibody Labeling Kits.

Preserve Primary Antibody Function and Affinities
Reactive dye labeling of primary antibodies can have unpredictable and undesirable outcomes. Among these are reduced binding affinities by label addition in the binding pocket. Zenon® antibody labeling approach, targeted to the Fc tail, avoids this concern.

Moreover the Zenon® dye- and enzyme-labeled Fab fragments have been affinity purified during their preparation to help ensure their high affinity and selectivity for the Fc portion of the corresponding primary antibody. The procedure for chemical labeling of the Fab fragments protects the Fc-binding site, resulting in more active labeling reagents.

Many Fluorophore and Enzyme Labels Available
Zenon® immunolabeling technology makes it very easy to change fluorescent color combinations or detection methodologies by simply using a different dye- or enzyme-labeled Fab fragment from our extensive selection of over 100 Zenon® Antibody Labeling Kits. If larger quantities or covalent attachment of the label is desired, see Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices.

Zenon® Technology Simplifies the Use of Multiple Antibodies of the Same Isotype in the Same Protocol
The stability of the Zenon® complex is sufficient to allow sequential (or simultaneous) labeling of different targets in cells and tissues with multiple antibody complexes. Subsequent to staining, an aldehyde-based fixation step can permanently block the transfer of Zenon® labels between different primary antibodies and will preserve the staining pattern.

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.

Related Links:

Zenon® Labeling Technology
Zenon® Technology: Versatile Reagents for Immunolabeling—Section 7.3

Alexa Fluor™ 750 NHS Ester (Succinimidyl Ester) (Invitrogen™)

Alexa Fluor® 750 is a bright and photostable near-IR dye that is spectrally similar to Cy7. Used for stable signal generation in imaging and flow cytometry, Alexa Fluor® 750 dye is water soluble and pH-insensitive from pH 4 to pH 10. Fluorescence of this long-wavelength Alexa Fluor® dye is not visible to the human eye but is readily detected by most imaging systems. In addition to reactive dye formulations, we offer Alexa Fluor® 750 dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection (learn more).

The NHS ester (or succinimidyl ester) of Alexa Fluor® 750 is the most popular tool for conjugating this dye to a protein or antibody. NHS esters can be used to label to the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting Alexa Fluor® conjugate will exhibit brighter fluorescence and greater photostability than the conjugates of other spectrally similar fluorophores.

Detailed information about this AlexaFluor® NHS ester:

Fluorophore label: Alexa Fluor® 750 dye
Reactive group: NHS ester
Reactivity: Primary amines on proteins and ligands, amine-modified oligonucleotides
Ex/Em of the conjugate: 753/782 nm
Extinction coefficient: 290,000 cm-1M-1
Spectrally similar dyes: Cy7
Molecular weight: ~1300

Typical Conjugation Reaction
You can conjugate amine-reactive reagents with virtually any protein or peptide (the provided protocol is optimized for IgG antibodies). You can scale the reaction for any amount of protein, but the concentration of the protein should be at least 2 mg/mL for optimal results. We recommend trying three different degrees of labeling, using three different molar ratios of the reactive reagent to protein.

The Alexa Fluor® NHS ester is typically dissolved in high-quality anhydrous dimethylformamide (DMF) or dimethylsulfoxide (DMSO) (D12345), and the reaction is carried out in 0.1–0.2 M sodium bicarbonate buffer, pH 8.3, at room temperature for 1 hour. Because the pKa of the terminal amine is lower than that of the lysine epsilon-amino group, you may achieve more selective labeling of the amine terminus using a buffer closer to neutral pH.

Conjugate Purification
Labeled antibodies are typically separated from free Alexa Fluor® dye using a gel filtration column, such as Sephadex™ G-25, BioGel® P-30, or equivalent. For much larger or smaller proteins, select a gel filtration media with an appropriate molecular weight cut-off or purify by dialysis. We offer several purification kits optimized for different quantities of antibody conjugate:
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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.

BODIPY™ TMR-X NHS Ester (Succinimidyl Ester) (Invitrogen™)

BODIPY® TMR-X dye is bright, orange fluorescent dye with similar excitation and emission to tetramethyrhodamine (TRITC) or Alexa Fluor® 555 dye. It has a high extinction coefficient and fluorescence quantum yield and is relatively insensitive to solvent polarity and pH change. In contrast to the highly water soluble fluorophores Alexa Fluor® 488 dye and fluorescein (FITC), BODIPY® dyes have unique hydrophobic properties ideal for staining lipids, membranes, and other lipophilic compounds. BODIPY® TMR-X dye has a relatively long excited-state lifetime (typically 5 nanoseconds or longer), which is useful for fluorescence polarization-based assays and a large two-photon cross-section for multiphoton excitation. In addition to reactive dye formulations, we offer BODIPY® TMR-X dye conjugated to a variety of antibodies, peptides, proteins, tracers, and amplification substrates optimized for cellular labeling and detection.

The NHS ester (or succinimidyl ester) of BODIPY® TMR-X is the most popular tool for conjugating the dye to a protein or antibody. NHS esters can be used to label the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting BODIPY® TMR-X conjugates exhibit bright fluorescence, narrow emission bandwidths, and relatively long excited-state lifetimes, which can be useful for fluorescence polarization assays and two-photon excitation (TPE) microscopy.

This reactive dye contains a seven-atom aminohexanoyl ("X") spacer between the fluorophore and the NHS ester group. This spacer helps to separate the fluorophore from its point of attachment, potentially reducing the interaction of the fluorophore with the biomolecule to which it is conjugated.

Detailed information about this BODIPY® TMR-X NHS ester:

Fluorophore label: BODIPY® TMR-X dye
Reactive group: NHS ester (succinimidyl ester)
Reactivity: Primary amines on proteins and ligands, amine-modified oligonucleotides
Ex/Em of the conjugate: 544/570 nm
Extinction coefficient: 60,000 cm-1M-1
Molecular weight: 608.45

Typical Conjugation Reaction
Amine-reactive reagents can be conjugated with virtually any protein or peptide; the provided protocol is optimized for IgG antibodies. The reaction can be scaled for any amount of protein, but the concentration of the protein should be at least 2 mg/mL for optimal results. We recommend trying three different degrees of labeling, using three different molar ratios of the reactive reagent to protein.

The BODIPY® NHS ester is typically dissolved in high-quality anhydrous dimethylformamide (DMF) or dimethylsulfoxide (DMSO), and the reaction is carried out in 0.1-0.2 M sodium bicarbonate buffer, pH 8.3, at room temperature for 1 hour. Because the pKa of the terminal amine is lower than that of the lysine epsilon-amino group, you may achieve more selective labeling of the amine terminus using a buffer closer to neutral pH.

Conjugate Purification
Labeled antibodies are typically separated from free BODIPY® dye using a gel filtration column, such as Sephadex™ G-25, BioGel® P-30, or equivalent. For much larger or smaller proteins, select a gel filtration medium with an appropriate molecular weight cut-off or purify by dialysis. We offer several purification kits optimized for different quantities of antibody conjugate:
Antibody Conjugate Purification Kit for 0.5-1 mg (A33086)
Antibody Conjugate Purification Kit for 20-50 µg (A33087)
Antibody Conjugate Purification kit for 50-100 µg (A33088)

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 our Antibody Labeling kits or use our Labeling Chemistry Selection Tool for other choices. To learn more about our labeling kits, read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in The Molecular Probes® Handbook.

We’ll Make a Custom Conjugate for You
If you can’t find what you’re looking for in our online catalog, we’ll prepare a custom antibody or protein 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™ 780-B1 NHS Ester (Thermo Scientific™)

Thermo Scientific DyLight near-infrared specialty dyes, comparable to Alexa Fluor and IRDye NIR dyes, can be used to label antibodies, peptides, and other proteins at primary amines. DyLight 780-B1 dye has a structure based on the benzopyrillium core, with 1 sulfonate. It has excitation and emission peaks at 783 and 799 nm, respectively (in ethanol).

General characteristics of DyLight near-infrared emitting specialty dyes:

Large selection—the largest family of dyes available for NIR fluorescence applications
NHS ester reactive group—allows immediate labeling of antibodies, proteins, peptides and other amine-containing molecules through amide bond formation
Broad spectrum of water solubilities—choose from hydrophilic to hydrophobic dyes to optimize the right dye label for the best performance in a given application
NIR dyes avoid background interference—DyLight NIR Dyes avoid fluorescence interference or quenching effects from biomolecules present in samples
Excellent signal penetration through cells and tissues—DyLight NIR Dyes provide the optimal window for excitation and emission for in vivo imaging applications

DyLight NIR Dyes are a family of labeling agents that can be used for bright fluorescence detection in cell-based imaging or in vivo imaging applications. NIR dyes can be selected based upon their characteristic excitation and emission properties or relative hydrophilicity and hydrophobicity attributes. Dyes that contain a greater number of negatively charged sulfonates generally will have greater water solubility than dyes with fewer sulfonates. More hydrophobic dyes often provide better cell penetrating ability in vivo, while more hydrophilic dyes have less nonspecific binding potential. Each dye contains an amine-reactive NHS ester for simple modification of antibodies, proteins, peptides or other biomolecules through amide bond formation. NIR dyes are best for imaging through tissues and away from indigenous fluorescent biomolecule interference or quenching. DyLight Near Infrared Dyes represent the largest selection of fluorescent labels that are commercially available.

Criteria to consider when choosing a DyLight NIR Specialty Dye
• Excitation and emission wavelengths—choose the best dye to match the excitation and emission capabilities of your instrument
• Water solubility—choose a DyLight NIR Dye based on its relative hydrophilicity, which directly correlates to the number of negatively-charged sulfonates it has on its core structure. More hydrophilic dyes are best at maintaining water solubility of a labeled antibody and limiting the nonspecific binding of the conjugate. More hydrophobic dyes often are best at penetrating tissues and cell membranes in vivo, meaning that dyes with fewer sulfonates may work best for some applications.
• DyLight Dye selection—the broad selection of NIR dyes allows a number of candidate dyes to be tested in a given application for optimal performance.

Applications:
In vivo or ex vivo imaging
• Tumor imaging with labeled peptides
• NIR fluorescence (NIRF) imaging of labeled silica nanoparticles
• NIR in vitro imaging and characterization
• Determination of thermal stability
• Cytotoxicity assays
• Molecular imaging
• UV-VIS-NIR spectroscopy
• Fluorescence correlation spectroscopy
• MRI applications
• DNA sequencing
• Primer labeling for PCR
• 2-D gel electrophoresis
• Flow cytometry/fluorescence-activated cell sorting (FACS)
• Laser scanning confocal microscopy

Related Products
DyLight™ 780-B2 NHS Ester
DyLight™ 780-B3 NHS Ester
DyLight™ 830-B2 NHS Ester

Qtracker™ 655 Vascular Labels (Invitrogen™)

Qtracker® non-targeted quantum dots are designed to be injected into the tail vein of mice for the study of vascular structure using small animal in vivo imaging (SAIVI) techniques. These nanocrystals exhibit intense fluorescence with red-shifted emission for increased tissue penetration, and have a PEG surface coating specially developed to minimize nonspecific interactions and reduce immune response by the tissue. Because the PEG surface coating does not contain reactive functional groups, the Qtracker® non-targeted quantum dots are retained in circulation longer and can be imaged for up to 3 hours with a single injection or for longer periods of time with additional injections.

Need a different emission spectrum or longer tracking? View our other mammalian cell tracking products.

Key Attributes:

Qtracker® 655 label has Ex/Em (405-615/655) nm
Designed for small animal in vivo imaging
Introduced via tail vein injection, can be imaged for up to 3 hours after injection
Available in four colors—565 nm, 655 nm, 705 nm, or 800 nm emission

Read more about SAIVI and about applications for Qdot® nanocrystals.

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

EZ-Link™ Phosphine-PEG3-Biotin (Thermo Scientific™)

Thermo Scientific Pierce EZ-Link Phosphine-PEG3-Biotin is a biotinylation reagent for labeling azide-containing molecules, which enables biotin-based detection and affinity purification of molecules via Staudinger ligation strategies.

Features of EZ-Link Phosphine-PEG3-Biotin:

Soluble—easily dissolves in water-miscible solvents (e.g., DMSO) for subsequent dilution in aqueous reaction mixtures with cell lysates and other biological samples
Compatible—reaction chemistry occurs effectively in simple buffer conditions; requires no accessory reagents such as copper or reducing agents
Chemoselective—the phosphine reactive group is specific in biological samples for bioorthogonal azide-tagged molecules, ensuring that biotinylation is specific
PEG spacer—polyethylene glycol spacer arm helps maintain solubility of labeled molecules and decreases steric hindrance for affinity-binding to avidin, streptavidin or NeutrAvidin Protein

When used in combination with azide labeling strategies, this compound enables detection or affinity purification of protein interactions and post-translational modifications using streptavidin probes or streptavidin agarose resins. The phosphine group of Phosphine-PEG3-Biotin conjugates to azide groups by the Staudinger reaction mechanism. Azide groups can be introduced into proteins or other cellular targets through in vivo labeling with azide-tagged derivatives of naturally occurring metabolic building blocks. Because neither phosphines nor azides are present in biological systems, they comprise a chemoselective (mutually specific) ligation pair for labeling and conjugation.

Zenon™ pHrodo™ iFL Red Human 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.

EZ-Link™ Iodoacetyl-PEG2-Biotin (Thermo Scientific™)

Thermo Scientific EZ-Link Iodoacetyl-PEG2-Biotin is a mid-length, haloacetyl-activated, sulfhydryl-reactive biotinylation reagent that contains a 2-unit ethylene glycol in its spacer arm for increased water-solubility characteristics.

Features of EZ-Link Iodoacetyl-PEG2-Biotin:

Protein labeling—biotinylate antibodies or other proteins for use in protein methods
Thiol-reactive—reacts with sulfhydryls (-SH), such as the side-chain of cysteine (C)
Iodoacetyl-activated—perform reactions in the dark at pH 7.5 to 8.5 in Tris or borate buffer
Pegylated—spacer arm contains a hydrophilic, 2-unit, polyethylene glycol (PEG) group
Enhances solubility—pegylation imparts water solubility to the biotinylated molecule, helping to prevent aggregation of biotinylated antibodies stored in solution
Irreversible—forms permanent thioether bonds; spacer arm cannot be cleaved
Solubility—can be dissolved directly in aqueous buffers for labeling reactions
Medium length—spacer arm (total length added to target) is 24.7 angstroms

Iodoacetyl-PEG2-Biotin enables simple and efficient biotin labeling of antibodies, cysteine-containing peptides and other thiol-containing molecules. The iodoacetyl group reacts with reduced thiols (sulfhydryl groups,—SH) at alkaline pH to form stable thioether bond. The hydrophilic, 2-unit polyethylene glycol (PEG) spacer arm imparts water solubility that is transferred to the biotinylated molecule, thus reducing aggregation of labeled proteins stored in solution. The PEG segment adds length and flexibility to the spacer arm, minimizing steric hindrance involved with binding to avidin molecules.

We manufacture biotin reagents to ensure the highest possible overall product integrity, consistency and performance for the intended research applications.

Biotinylation reagents differ in reactivity, length, solubility, cell permeability and cleavability. Three types of sulfhydryl-reactive compounds are available: maleimido, iodoacetyl and pyridyldithiol. Iodoacetyl reagents specifically react with sulfhydryl groups (-SH) at pH 8.3 to form permanent thioether bonds.

In proteins, sulfhydryls exist where there are cysteine (C) residues. Cystine disulfide bonds must be reduced to make sulfhydryl groups available for labeling. Hinge-region disulfide bridges of antibodies can be selectively reduced to make functional half-antibodies that can be labeled.

Click-iT™ Alexa Fluor™ 647 sDIBO Alkyne for Antibody Labeling (Invitrogen™)

The Click-iT Alexa Fluor 647 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.

GlycanAssure™ AutoXpress Kit with CE Module

The GlycanAssure AutoXpress Kit is designed for use on the AutoMate Express System for GlycanAssure AutoXpress Kits, for hands-free automation of the preparation of labelled glycans from glycoprotein samples. The kit includes GlycanAssure AutoXpress cartridges that contain pre-filled reagents and plastic tubes and tips to perform hands-free glycan release and labelling of up to 13 samples in one run. This version of the kit contains a CE module with additional chemistries needed for CE analysis.

The GlycanAssure AutoXpress cartridge reagents are based on the established GlycanAssure chemistry for N-glycan rapid release, labeling, and cleanup that applies a novel method for N-glycan release in a complete form. The GlycanAssure APTS N-glycan sample prep method consists of rapid deglycosylation using PNGase-F enzyme followed by magnetic bead-based glycan purification, glycan labeling with ATPS dye, and excess dye removal. The GlycanAssure AutoXpress Kit combined with the AutoMate Express System offers a single, automated N-glycan sample prep workflow for both high throughput (CE) and characterization (UHPLC) biopharma applications.

Key features of the combined kit/system include:
• Fully automated sample prep for N-glycan analysis
• Rapid results with cartridge-based reagents for glycan release and labelling
• High quality glycan data with reduced analyst error
• Labeled glycans can be analyzed on LC or CE platforms
• Small system footprint and low-cost automation platform make it adaptable in both development and QC labs
• Consistent data for easy method development and transfer across the globe

DyLight™ 488-Phosphine (Thermo Scientific™)

Thermo Scientific DyLight Fluor Phosphine Reagents are phosphine-activated fluorescent dyes for specific labeling and detection of azide-tagged molecules, which enables use of fluorescence imaging in metabolic labeling strategies.

When used in combination with azide labeling strategies, phosphine-activated DyLight Fluors enable selective fluorescent labeling for detection of protein interactions and post-translational modifications using fluorescence imaging technologies. The phosphine group conjugates to azide groups by the Staudinger reaction mechanism. Azide groups can be introduced into proteins or other cellular targets through in vivo labeling with azide-tagged derivatives of naturally occurring metabolic building blocks. Because neither phosphines nor azides are present in biological systems, they comprise a chemoselective (mutually specific) ligation pair for labeling and conjugation.

General features of the phosphine-activated DyLight Fluors:

Soluble—easily dissolves in water-miscible solvents (e.g., DMSO) for subsequent dilution in aqueous reaction mixtures with cell lysates and other biological samples
Compatible—reaction chemistry occurs effectively in simple buffer conditions; requires no accessory reagents such as copper or reducing agents, and does not interfere with fluorescence applications
Chemoselective—the phosphine reactive group is specific in biological samples for bioorthogonal azide-tagged molecules, ensuring that fluorescent labeling is specific
High-performance fluorescence—DyLight 488, 550 and 650 are intense, highly stable fluorophores for green, orange and red fluorescent detection. (see DyLight Fluors)

Related Products
DyLight™ 550-Phosphine
DyLight™ 650-Phosphine