Instruction manual

First Edition (Revised on April, 2016)


Streptavidin is a kind of biotin binding protein derived from Streptomyces Avidin, which nonspecific binding is much lower than avidin. The egg white avidin has a net positive charge at neutral pH and contains about 7% carbohydrate, while the Streptavidin has little or no net charge at neutral pH and does not contain carbohydrates. Therefore, it is widely used instead of avidin. Structurally, streptavidin exists in the form of homologous tetramers, and can bind four moles of biotin molecules per mole, which makes it widely used in various signal amplification systems for biochemical and immunological detection. In addition, the product can also be used for the labeling of a variety of enzymes and compounds, the protein purification and detection by biotinylated antibodies.



Source: Eukaryotic expression.

Host: E.coli

Purity: >95%.

Endotoxin: <1.0 EU/mL as determined by the LAL method.

Traits: Freeze-dried powder. (Liqid form can be provided as required)

Molecular Mass: 14kDa&60kDa

Buffer formulation: PBS, pH 7.4.

Original Concentration: 1.0 mg/mL.

Applications: SDS-PAGE; WB; IHC; ELISA; CLIA; Flow Cytometry; In situ hybridization. (May be suitable for use in other assays to be determined by the end user.) 


[ Activity ]

>16 U/mg(1 unit is defined as the amount of protein required to bind 1.0 µg of 1ug D-biotin)


Reconstitute the protein with 1mL deionized or distilled water to 1.0 mg/mL. Do not vortex.


Storage: Avoid repeated freeze/thaw cycles.

                      Store at -20oC for 12 months as supplied (Lyophilized form) .

            Store at 2-8oC for 1 month, or -20oC for 3 months after reconstitution.

Stability Test: The stability is described by the loss rate. The loss rate was determined by stability test and accelerated thermal degradation test, that is, incubate the protein at 4oC for a week, and no obvious degradation and precipitation were observed; incubate the protein at 37oC for a week, and the loss rate is less than 5%.