ACTIVE ENZYME DETECTION USING IMMOBILIZED ENZYME INHIBITORS

摘要

The present method utilizes the capture of the functionally active form of an enzyme that covalently binds or binds with a dissociation constant of 1 x 10<-9>M or less to an enzyme inhibitor or mutant thereof. The present invention is directed to a method for detecting a functionally active form of an enzyme in a biological sample, comprising contacting an enzyme inhibitor or mutant thereof immobilized on a solid substrate with the biological sample, and measuring the binding of the enzyme inhibitor or mutant thereof to the active form of the enzyme by a detectable label. Specific enzyme inhibitors or mutants thereof are designed to covalently bind to specific clinically important enzymes. These enzyme inhibitors contain modifications that affect the binding to a target enzyme or affect the stability or the inhibitor. The nethod is particularly useful in measuring the presence of enzymes, such as tPA, elastase, cathepsin G and prostate specific antigen.