If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 or view local office numbers.
Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.
This product is soluble in water or aqueous buffer (i.e., PBS) at 1 mg/mL. Solutions in PBS or water can be stored for several months at 4°C, or for more than a year as frozen aliquots.
On the Certificate of Analysis for the product, the activity of the product per milligram can be found. This number is specific for your lot, and you must look up the Certificate of Analysis by the lot number for your particular batch of product. From this number, you can calculate how many units are in a particular weight of your product by multiplying the weight of the product by the units/mg of the product.
Product No. S4762 has not been assigned an expiration date by Sigma. Streptavidin is stable. S4762 has been assigned a QC Release date as well was a Retest Date. These dates can be found on the Certificate of Analysis. The QC Release Date indicates the last date that the lot was tested and found to meet specifications, and the Retest Date indicates the next date that the lot will be tested, assuming that enough of the lot remains to perform the testing.
Streptavidin binds the small molecule biotin with extraordinary affinity. The dissociation constant is KD = 4 × 10-14 M, according to N. M. Green, Methods Enzymol., 184, 51 (1990).
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