Streptavidin (SA) is produced by Streptomyces avidinii and isolated by purification from fermentation broth.
The molecule of streptavidin consists of 4 identical subunits, each bearing an active binding site for the vitamin biotin.
- High affinity – binds 4 moles of biotin per mole of protein
- Fast reacting – due to high affinity of the biotin-streptavidin interaction
- Typically used in combination with biotinylated antibodies in order to obtain amplified signals detecting sub-nanogram amounts of antigen.
- Can also be coated directly on the solid phase in the first step of an ELISA and used as a generic capture system for biotinylated antibodies with poor coating properties. Having plates pre-coated with streptavidin reduces the need for developing new coating methods.
- BSA free
- Free of azide, mercury or other toxic preservative formulations
- White lyophilized powder
- Lyophilized in 50 mM NaCl (pH 9.0)
- Activity > 13 U/mg (one unit binds 1 μg of biotin)
- Purity: SDS – 1 band (non-reduced)
- Molecular weight: 55.000 Dalton
- Ip: slightly acidic, 5-6
- No detectable decomposition within 18 months when stored dry at -20°C
- Stable over a wide range of pH and decomposes only in the presence of SDS > 60°C
All products are available as OEM components or under our own Kem-En-Tec Diagnostics A/S label.