The use of NN-dimethylcasein in the determination of proteolytic enzymes in washing products and airborne dust samples

Abstract

NN-Dimethylcasein is used as substrate in an automatic method for the determination of proteolytic enzymes in washing products and airborne dust samples. Amino-acids formed by reaction with the enzyme are caused to react with 2,4,6-trinitrobenzenesulphonic acid to form stable, coloured Meisenheimer complexes. As NN-dimethylcasein does not react with trinitrobenzenesulphonic acid there is not need to remove excess of substrate before colour development, and the enzyme digestion and colour reactions can be conducted simultaneously. This leads to high sensitivity, which is of particular value in dust analysis and allows the use of a simple trouble-free manifold.