N-p-Tosyl-Gly-Pro-Lys-pNA is a colorimetric substrate for plasmin.1,2,3 Plasmin binds and hydrolyzes N-p-tosyl-Gly-Pro-Lys-pNA to release p-nitroanilide (pNA), which can be quantified by colorimetric detection at 405 nm as a measure of plasmin activity.
1.Jespersen, J., Gram, J., and Astrup, T.The autodigestion of human plasmin follows a bimolecular mode of reaction subject to product inhibitionThromb. Res.41(3)395-404(1986) 2.Kim, S.H., and Choi, N.S.Electrophoretic analysis of protease inhibitors in fibrin zymographyAnal. Biochem.270(1)179-181(1999) 3.Chen, T., and Rael, E.D.Purification of M5, a fibrinolytic proteinase from Crotalus molossus molossus venom that attacks complementInt. J. Biochem. Cell Biol.29(5)789-799(1997)