Eye Irrit. 2 - Resp. Sens. 1 - Skin Irrit. 2 - STOT SE 3
11 - Combustible Solids
dust mask type N95 (US), Eyeshields, Faceshields, Gloves
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.
Trypsin is soluble in 1 mM hydrochloric acid (pH approximately 3). It is also surprisingly stable in 1 mM HCl. Solutions are stable for approximately 1 year when aliquoted and stored at -20°C. The presence of Ca2+ (20 mM) will also retard trypsin's ability to autodigest, and will therefore help to maintain the stability of the trypsin in solution.
For trypsin digestion of peptides, use a ratio (w:w) of about 1:100 to 1:20 for trypsin:peptide. Trypsin preparations usually contain some contaminating chymotrypsin and this should be inhibited with N-tosyl-L-phenylalanyl chloromethyl ketone (TPCK). Product No. T1426 has already been treated with TPCK, so it does not need to be further treated.
Various values have been reported in the literature for the extinction coefficient of bovine pancreatic trypsin. The E1%(280) values have ranged from 12.9 - 15.4. When we assay the protein content of Product No. T1426 in our labs here at Sigma, we use a value of 14.4.
For in-gel digestions, we actually recommend using a methylated trypsin. Product No. T6567 is Trypsin from porcine pancreas, proteomics grade, dimethylated. For product T6567, the lysine residues of proteomics grade trypsin have been reductively methylated, resulting in a product that is resistant to autolysis. The T6567 has also been treated with TPCK to remove chymotryptic activity, further purified through affinity chromatography, and lyophilized. This results in an enzyme that gives highly specific cleavage.
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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.
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