Streptavidin-Xtra™ IF647

Streptavidin conjugates are widely used in combing with biotin conjugates for detecting a variety of biological targets such as proteins, nucleic acids and other molecules. They are used as an ideal choice for many biological detections such as immunofluorescence microscopy, flow cytometry, western blot and other biological applications since streptavidin has a strong affinity binding biotin which is not affected over a broad range of pH and temperature. AAT Bioquest® offers a variety of streptavidin conjugates labeled with the classic fluorescent dyes (for example: FITC, TRITC, Texas Red®, Cy3®, Cy5® and Cy7®) and also our superior water soluble, photostable iFluor® and mFluor™ dyes. However, the conventional biotin-avidin detection systems are still limited by the limited signal intensity of the existing fluorescent conjugates. The Streptavidin Xtra™ iFluor conjugates are a new family of super bright streptavidin conjugates with nearly identical excitation and emission properties to Alexa Fluor fluorophores with 3~5 folds signal improvement. It is a set of powerful tools to detect low abundance targets in cell imaging or flow cytometry.

Images of Hela cells stained with Streptavidin-Xtra™ iFluor® conjugates and Streptavidin Alexa Fluor ™ conjugate.<br />Hela cells were fixed with 4% paraformaldehyde for 30 minutes, permeabilized with 0.02% Triton™ X-100 for 10 minutes, and blocked with 1% BSA for 1 hour. Fixed Hela cells were then stained with 1 µg/mL alpha Tubulin Mouse Monoclonal Antibody for 1 hour at room temperature, followed by GxM IgG-biotin (Cat# 16729) stain and then visualized with Streptavidin-Xtra™ iFluor 647 and Streptavidin-Alexa Fluor™ 647.  Cell nuclei were stained with Hoechst 33342 (Blue, Cat#17535).

Protocol

COA

Catalog	Size	Price	Quantity
46006	100 ug	Price
46007	1 mg	Price

Citations

View all 36 citations: Citation Explorer

Preexisting antibodies targeting SARS-CoV-2 S2 cross-react with commensal gut bacteria and impact COVID-19 vaccine induced immunity

Authors:

Jia, Liqiu and Weng, Shufeng and Wu, Jing and Tian, Xiangxiang and Zhang, Yifan and Wang, Xuyang and Wang, Jing and Yan, Dongmei and Wang, Wanhai and Fang, Fang and others,

Journal:

Gut microbes (2022): 2117503

Highly sensitive electrochemical biosensor for streptavidin detection based on CdSe quantum dots

Authors:

Wei, Y. P., Liu, X. P., Mao, C. J., Niu, H. L., Song, J. M., Jin, B. K.

Journal:

Biosens Bioelectron (2018): 99-103

Efficient streptavidin-functionalized nitrogen-doped graphene for the development of highly sensitive electrochemical immunosensor

Authors:

Yang, Z., Lan, Q., Li, J., Wu, J., Tang, Y., Hu, X.

Journal:

Biosens Bioelectron (2017): 312-318

High-sensitive surface plasmon resonance microRNA biosensor based on streptavidin functionalized gold nanorods-assisted signal amplification

Authors:

Hao, K., He, Y., Lu, H., Pu, S., Zhang, Y., Dong, H., Zhang, X.

Journal:

Anal Chim Acta (2017): 114-120

Correction to Peptide Tag-Induced Horseradish Peroxidase-Mediated Preparation of a Streptavidin-Immobilized Redox-Sensitive Hydrogel

Authors:

Mishina, M., Minamihata, K., Moriyama, K., Nagamune, T.

Journal:

Biomacromolecules (2017): 311

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)	250000 ¹
Excitation (nm)	656
Emission (nm)	670
Quantum yield	0.25 ¹

Storage, safety and handling

Intended use

Research Use Only (RUO)

Instrument settings

Flow cytometer
Excitation	633 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

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 October 13, 2025