Streptavidin, a 60 kDa tetrameric protein purified from Streptomyces avidinii, is composed of four identical subunits each containing a single binding site for biotin. In contrast to egg white avidin, streptavidin has a near neutral isoelectric point and does not contain carbohydrate side chains. These characteristics reduce the non-specific binding sometimes observed with avidin and permit the use of streptavidin for very sensitive immunoassays.
Streptavidin is conjugated to Rhodamine Red X achieving an F/P molar ratio between 2 - 5. Rhodamine has an absorbance maximum at 570 nm with an emission maximum at 590 nm.
Rhodamine RED X is a small fluorescent organic molecule with an absorbance maximum of 570 nm and an emission maximum of 590 nm.
0.01 M Phosphate Buffered Saline, 0.25 NaCl, pH 7.6 containing 15 mg/ml BSA (IgG free) and 0.05% Sodium Azide.
Reconstitute in 0.65 ml of highly pure deionized water. If extended storage is desired add 50% v/v glycerol (ACS grade or better).
Storage and Stability
Store the lyophilized powder at 2-8°C. Product is stable for ~6 weeks at 2-8°C as an undiluted liquid. If glycerol is added, the product can be stored at -20°C.
Applications and Suggested Working Dilutions
Country of Origin
Products are for research use only. Not for use in diagnostic or therapeutic procedures.
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