A VERSATILE MICROASSAY FOR ELASTASE USING SUCCINYLATED ELASTIN

We have developed a rapid, versatile, and sensitive elastase assay tha t is based on the measurement of primary amines that ape exposed due t o enzymatic degradation of proteins, using succinylated elastin as the substrate for elastase. After incubation with elastase the degree of digestion is determined with trinitrobenzene sulfonic acid. The assay is rapid and sensitive, detecting elastase down to 1 ng/ml, and is lin ear up to enzyme concentrations of 10 mu g/ml. The assay is carried ou t in microtiter plate wells and therefore offers the potential for ass aying numerous samples of small volume. The use of succinylated elasti n shows specificity for elastase over the control protease, trypsin. T his assay is also versatile because it can be applied to samples such as cell culture supernatants, blood plasma, tissue biopsies, and tissu e homogenates. (C) 1997 Academic Press.