Shop All Streptavidin & Conjugates

Streptavidin, Alexa Fluor™ 647 conjugate (Invitrogen™)

Alexa Fluor® 647 streptavidin comprises a biotin-binding protein (streptavidin) covalently attached to a fluorescent label (Alexa Fluor® dye). Streptavidin has a very high binding affinity for biotin, and a conjugate of streptavidin is commonly used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids, and other molecules (for example, a biotinylated primary antibody bound to a protein target can be detected with a fluorescently labeled streptavidin). Strategies similar to this are used in many detection protocols including western blots, flow cytometry, imaging and microscopy, and microplate assays. Alexa Fluor® dye streptavidin conjugates are supplied as 1 mg lyophilized product or in 0.5 mL volumes of a 2 mg/mL solution.

Important Features of Alexa Fluor® 647 Streptavidin Conjugates:
Alexa Fluor® 647 streptavidin conjugate has Ex/Em maxima of ~ (650/668)
Bright, photostable fluorescence
High solubility in aqueous solutions
Available in multiple colors
Ideal for western blots, flow cytometry, imaging and microscopy, microplate assays and more

Properties of Alexa Fluor® Dyes
Alexa Fluor® dyes are organic fluorescent dyes developed for better performance in imaging and other labeling protocols and exhibit improved photostability and brightness and improved solubility in aqueous solutions. Available in a broad range of colors, these dyes are a good choice for most imaging applications.

Blocking Endogenous Biotin
Naturally occurring biotins can interfere with biotin-streptavidin detection schemes. For experiments involving fixed and permeabilized cells, try our Endogenous Biotin-Blocking Kit to minimize this interference.

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

Related Links:

Learn more about Avidin-Biotin Detection

Learn more about Alexa Fluor® Dyes

Find out about other Labeled Streptavidin Conjugates

Read Avidin and Streptavidin Conjugates-Section 7.6 in the Molecular Probes Handbook

Streptavidin, Alexa Fluor™ 633 conjugate (Invitrogen™)

Alexa Fluor® 633 streptavidin comprises a biotin-binding protein (streptavidin) covalently attached to a fluorescent label (Alexa Fluor® dye). Streptavidin has a very high binding affinity for biotin, and a conjugate of streptavidin is commonly used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids, and other molecules (for example, a biotinylated primary antibody bound to a protein target can be detected with a fluorescently labeled streptavidin). Strategies similar to this are used in many detection protocols including western blots, flow cytometry, imaging and microscopy, and microplate assays. Alexa Fluor® dye streptavidin conjugates are supplied as 1 mg lyophilized product or in 0.5 mL volumes of a 2 mg/mL solution.

Important Features of Alexa Fluor® 633 Streptavidin Conjugates:
Alexa Fluor® 633 streptavidin conjugate has Ex/Em maxima of ~ (632/647)
Bright, photostable fluorescence
High solubility in aqueous solutions
Available in multiple colors
Ideal for western blots, flow cytometry, imaging and microscopy, microplate assays and more

Properties of Alexa Fluor® Dyes
Alexa Fluor® dyes are organic fluorescent dyes developed for better performance in imaging and other labeling protocols and exhibit improved photostability and brightness and improved solubility in aqueous solutions. Available in a broad range of colors, these dyes are a good choice for most imaging applications.

Blocking Endogenous Biotin
Naturally occurring biotins can interfere with biotin-streptavidin detection schemes. For experiments involving fixed and permeabilized cells, try our Endogenous Biotin-Blocking Kit to minimize this interference.

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

Related Links:

Learn more about Avidin-Biotin Detection

Learn more about Alexa Fluor® Dyes

Find out about other Labeled Streptavidin Conjugates

Read Avidin and Streptavidin Conjugates-Section 7.6 in the Molecular Probes Handbook

Streptavidin, Alexa Fluor™ 660 conjugate (Invitrogen™)

Alexa Fluor® 660 streptavidin comprises a biotin-binding protein (streptavidin) covalently attached to a fluorescent label (Alexa Fluor® dye). Streptavidin has a very high binding affinity for biotin, and a conjugate of streptavidin is commonly used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids, and other molecules (for example, a biotinylated primary antibody bound to a protein target can be detected with a fluorescently labeled streptavidin). Strategies similar to this are used in many detection protocols including western blots, flow cytometry, imaging and microscopy, and microplate assays. Alexa Fluor® dye streptavidin conjugates are supplied as 1 mg lyophilized product or in 0.5 mL volumes of a 2 mg/mL solution.

Important Features of Alexa Fluor® 660 Streptavidin Conjugates:
Alexa Fluor® 660 streptavidin conjugate has Ex/Em maxima of ~ (663/690)
Bright, photostable fluorescence
High solubility in aqueous solutions
Available in multiple colors
Ideal for western blots, flow cytometry, imaging and microscopy, microplate assays and more

Properties of Alexa Fluor® Dyes
Alexa Fluor® dyes are organic fluorescent dyes developed for better performance in imaging and other labeling protocols and exhibit improved photostability and brightness and improved solubility in aqueous solutions. Available in a broad range of colors, these dyes are a good choice for most imaging applications.

Blocking Endogenous Biotin
Naturally occurring biotins can interfere with biotin-streptavidin detection schemes. For experiments involving fixed and permeabilized cells, try our Endogenous Biotin-Blocking Kit to minimize this interference.

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

Related Links:

Learn more about Avidin-Biotin Detection

Learn more about Alexa Fluor® Dyes

Find out about other Labeled Streptavidin Conjugates

Read Avidin and Streptavidin Conjugates-Section 7.6 in the Molecular Probes Handbook

Streptavidin, (PE-Cy5.5) (Invitrogen™)

Class: RUO
Statement: For research use only. Not for use in diagnostic procedures.
Buffer: PBS
Preservative: 0.1% Sodium Azide

View a selection guide for all streptavidin RPE, APC, and tandem conjugates.

Streptavidin, tetramethylrhodamine conjugate (Invitrogen™)

The streptavidin, tetramethylrhodamine conjugate has excitation and emission maxima ~555/580 and is widely used to detect biotinylated probes by fluorescence microscopy.

Streptavidin - Cy5 (Invitrogen™)

Reactivity: CY5-SA reacts with biotin.

Streptavidin, Alexa Fluor™ 680 conjugate (Invitrogen™)

Alexa Fluor® 680 streptavidin comprises a biotin-binding protein (streptavidin) covalently attached to a fluorescent label (Alexa Fluor® dye). Streptavidin has a very high binding affinity for biotin, and a conjugate of streptavidin is commonly used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids, and other molecules (for example, a biotinylated primary antibody bound to a protein target can be detected with a fluorescently labeled streptavidin). Strategies similar to this are used in many detection protocols including western blots, flow cytometry, imaging and microscopy, and microplate assays. Alexa Fluor® dye streptavidin conjugates are supplied as 1 mg lyophilized product or in 0.5 mL volumes of a 2 mg/mL solution.

Important Features of Alexa Fluor® 680 Streptavidin Conjugates:
Alexa Fluor® 680 streptavidin conjugate has Ex/Em maxima of ~ (679/702)
Bright, photostable fluorescence
High solubility in aqueous solutions
Available in multiple colors
Ideal for western blots, flow cytometry, imaging and microscopy, microplate assays and more

Properties of Alexa Fluor® Dyes
Alexa Fluor® dyes are organic fluorescent dyes developed for better performance in imaging and other labeling protocols and exhibit improved photostability and brightness and improved solubility in aqueous solutions. Available in a broad range of colors, these dyes are a good choice for most imaging applications.

Blocking Endogenous Biotin
Naturally occurring biotins can interfere with biotin-streptavidin detection schemes. For experiments involving fixed and permeabilized cells, try our Endogenous Biotin-Blocking Kit to minimize this interference.

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

Related Links:

Learn more about Avidin-Biotin Detection

Learn more about Alexa Fluor® Dyes

Find out about other Labeled Streptavidin Conjugates

Read Avidin and Streptavidin Conjugates-Section 7.6 in the Molecular Probes Handbook

Streptavidin Protein, PE (Invitrogen™)

Streptavidin for Western Blot, IHC, ELISA

Streptavidin, Pacific Blue™ conjugate (Invitrogen™)

Our streptavidin, Pacific Blue™ conjugate is a bright, blue-fluorescent probe with excitation/emission ~410/455 nm. Streptavidin is a nonglycosylated biotin-binding protein that is isolated from bacteria and has a near-neutral isoelectric point. It is widely used to detect biotinylated probes, because it reportedly exhibits less nonspecific binding than does the glycosylated, biotin-binding protein, avidin.

View a selection guide for all Alexa Fluor® streptavidin and avidin conjugates.

Streptavidin, Texas Red™ conjugate (Invitrogen™)

The streptavidin, Texas Red® conjugate has excitation and emission maxima ~596/612 and is widely used to detect biotinylated probes by fluorescence microscopy.

Streptavidin, R-Phycoerythrin Conjugate (SAPE) - 1 mg/mL (Invitrogen™)

Streptavidin is a bacterially derived biotin-binding protein that exhibits less nonspecific binding than avidin. Phycoerythrin also known as R-Phycoerythrin (RPE) is an intensely bright phycobiliprotein isolated from red algae with absorption maxima at approximately 496, 546 and 565 nm, and a fluorescence emission maximum of ~578 nm. Used in flow, microplate assays and microarrays, this has remained one of our top three selling products for decades—a proven performer that you can trust.

Important Features of Streptavidin RPE
• Biotin Detection with high quantum efficiency photoprotein
• 5–10 times brighter than organic fluors
• High water solubility
• Ideal for Flow, microarrays and microplate assays
• Also available as Premium grade with higher purity confirmed by HPLC (S21388)

Streptavidin and RPE
The high affinity of avidin, an egg-white protein, for biotin was first exploited in histochemical applications in the mid-1970s. Avidin, and its bacterial counterpart, streptavidin (from Streptomy cesavidinii), have since become standard reagents for diverse detection schemes. Streptavidin, a nonglycosylated 52,800-dalton protein, exhibits less nonspecific binding than avidin.

Rhodophyta Phycoerythrin (RPE) has a MW of 240,000 Daltons and has a quantum efficiency of 78% making it an incredibly bright reagent. However, the photostability is extremely poor and is not traditionally recommended for microscopy. But the broad absorption and bright orange signal may it ideal for flow, microplate and microarray applications whenever sensitive detection of biotins is required.

Learn more about avidin biotin detection in general

Learn more about SAV-RPE

Streptavidin Protein, DyLight 680 (Invitrogen™)

Streptavidin for Western Blot, IF, ICC, IHC, IP, ELISA

LanthaScreen™ Eu-Streptavidin

A general reagent for use in assay development, the Europium-Streptavidin binds to biotinylated peptide or physiological protein substrates.

Streptavidin, Alexa Fluor™ 488 conjugate (Invitrogen™)

Alexa Fluor® 488 streptavidin comprises a biotin-binding protein (streptavidin) covalently attached to a fluorescent label (Alexa Fluor® dye). Streptavidin has a very high binding affinity for biotin, and a conjugate of streptavidin is commonly used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids, and other molecules (for example, a biotinylated primary antibody bound to a protein target can be detected with a fluorescently labeled streptavidin). Strategies similar to this are used in many detection protocols including western blots, flow cytometry, imaging and microscopy, and microplate assays. Alexa Fluor® dye streptavidin conjugates are supplied as 1 mg lyophilized product or in 0.5 mL volumes of a 2 mg/mL solution.

Important Features of Alexa Fluor® 488 Streptavidin Conjugates:
Alexa Fluor® 488 streptavidin conjugate has Ex/Em maxima of ~ (495/519)
Bright, photostable fluorescence
High solubility in aqueous solutions
Available in multiple colors
Ideal for western blots, flow cytometry, imaging and microscopy, microplate assays and more

Properties of Alexa Fluor® Dyes
Alexa Fluor® dyes are organic fluorescent dyes developed for better performance in imaging and other labeling protocols and exhibit improved photostability and brightness and improved solubility in aqueous solutions. Available in a broad range of colors, these dyes are a good choice for most imaging applications.

Blocking Endogenous Biotin
Naturally occurring biotins can interfere with biotin-streptavidin detection schemes. For experiments involving fixed and permeabilized cells, try our Endogenous Biotin-Blocking Kit to minimize this interference.

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

Related Links:

Learn more about Avidin-Biotin Detection

Learn more about Alexa Fluor® Dyes

Find out about other Labeled Streptavidin Conjugates

Read Avidin and Streptavidin Conjugates-Section 7.6 in the Molecular Probes Handbook

Streptavidin - Agarose (Invitrogen™)

Reactivity: SA-Seph 4B reacts with biotin.