Conditions are developed for determining potential activity of plasminogen in amine groups formed in casein hydrolysis. Two variants of determination are suggested: by means of a ninhydrin reagent and trinitrobenzene sulphoacid. The method permits determining 0.02-0.1 of plasmin casein units (cas. units); it is 20 times as sensitive as the known caseinolytic method based on determination of the degree of tyrosine absorption.
Caseins Colorimetry