iFluor® 647-streptavidin conjugate

iFluor® 647-streptavidin conjugate is a far-red fluorescent probe designed for detecting biotinylated proteins, antibodies, nucleic acids, and other biomolecules through high-affinity streptavidin-biotin binding.

Binding Specificity: Exhibits high-affinity binding to biotinylated targets.
Spectral Properties: Excitation/emission maxima of 655/670 nm.
Filter Compatibility: Compatible with 640 nm laser excitation (APC channel) and Cy5 microscope filter sets.
Applications: Suitable for indirect immunofluorescence staining and biotin-streptavidin-based assays.

HeLa cells were incubated with mouse anti-tubulin and biotin goat anti-mouse IgG followed by AAT’s iFluor® 647-streptavidin conjugate (Red, Left) or streptavidin conjugated with Alexa Fluor<sup>®</sup> 647 (Red, Right), respectively.

Protocol

Catalog	Size	Price	Quantity
16966	200 ug	Price
16996	1 mg	Price

Overview

AAT Bioquest's iFluor® dyes are optimized for labeling proteins, in particular, antibodies. These dyes are bright, photostable and have minimal quenching on proteins. They can be well excited by the major laser lines of fluorescence instruments (e.g., 350, 405, 488, 555 and 633 nm). Streptavidin conjugates are widely used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids and other molecules since streptavidin has a very high binding affinity for biotin. A variety of the complementary biotinylated reagents are available from numerous commercial vendors.This iFluor® 647-streptavidin conjugate comprises streptavidin (as the biotin-binding protein) with iFluor® 647 covalently attached (as the fluorescent label). It is commonly used as a second step reagent for indirect immunofluorescent staining, when used in conjunction with biotinylated primary antibodies. iFluor® 647-streptavidin conjugates has fluorescence excitation and emission maxima of ~654 nm and ~674 nm respectively. These spectral characteristics make it an excellent alternative to Alexa Fluor® 647-streptavidin conjugate (Alexa Fluor® is the trademark of Invitrogen). It is a very valuable tool for biotin-streptavidin-based biological assays and tests.

Citations

View all 2 citations: Citation Explorer

Rational Strategy for Designing Peptidomimetic Small Molecules Based on Cyclic Peptides Targeting Protein--Protein Interaction between CTLA-4 and B7-1

Authors:

Tsuihiji, Kumiko and Honda, Eiji and Kojoh, Kanehisa and Katoh, Shizue and Taguri, Tomonori and Yoshimori, Atsushi and Takashima, Hajime

Journal:

Pharmaceuticals (2022): 1506

Overexpression of MACC1 and the association with hepatocyte growth factor/c-Met in epithelial ovarian cancer

Authors:

Li, Hongyu and Zhang, Hui and Zhao, Shujun and Shi, Yun and Yao, Junge and Zhang, Yanyan and Guo, Huanhuan and Liu, Xingsuo

Journal:

Oncology letters (2015): 1989--1996

References

View all 47 references: Citation Explorer

A streptavidin paramagnetic-particle based competition assay for the evaluation of the optical selectivity of quadruplex nucleic acid fluorescent probes

Authors:

Largy E, Hamon F, Teulade-Fichou MP.

Journal:

Methods. (2012)

Biotin-4-fluorescein based fluorescence quenching assay for determination of biotin binding capacity of streptavidin conjugated quantum dots

Authors:

Mittal R, Bruchez MP.

Journal:

Bioconjug Chem (2011): 362

Iminobiotin binding induces large fluorescent enhancements in avidin and streptavidin fluorescent conjugates and exhibits diverging pH-dependent binding affinities

Authors:

Raphael MP, Rappole CA, Kurihara LK, Christodoulides JA, Qadri SN, Byers JM.

Journal:

J Fluoresc (2011): 647

Streptavidin-Binding Peptide (SBP)-tagged SMC2 allows single-step affinity fluorescence, blotting or purification of the condensin complex

Authors:

Kim JH, Chang TM, Graham AN, Choo KH, Kalitsis P, Hudson DF.

Journal:

BMC Biochem (2010): 50

Determination of 17beta-oestradiol by fluorescence immunoassay with streptavidin-conjugated quantum dots as label

Authors:

Sun M, Du L, Gao S, Bao Y, Wang S.

Journal:

Steroids (2010): 400

Physical properties

Molecular weight	~52000
Solvent	Water

Spectral properties

Correction factor (260 nm)	0.03
Correction factor (280 nm)	0.03
Correction factor (656 nm)	0.0793
Extinction coefficient (cm ^-1 M ^-1)	220000 ¹
Excitation (nm)	655
Emission (nm)	670
Quantum yield	0.25 ¹

Usage and storage

Intended use	Research Use Only (RUO)
Storage	Freeze (< -15 °C); Minimize light exposure

Instrument settings

Flow cytometer
Excitation	640 nm laser
Emission	660/20 nm filter
Instrument specification(s)	APC channel

Fluorescence microscope
Excitation	Cy5 filter set
Emission	Cy5 filter set
Recommended plate	Black wall/clear bottom
Instrument specification(s)	Cy5 filter set

Telephone
Fax
Email	sales@aatbio.com
International	See distributors
Bulk request	Inquire
Custom size	Inquire
Technical support	Contact us
Request quotation	Request
Purchase order	Send to sales@aatbio.com
Shipping	Standard overnight for United States, inquire for international

Page updated on November 14, 2026