The determination of acid phosphatase of prostatic origin with the Automatic Clinical Analyzer (ACA, DuPont).

A critical evaluation of the determination of acid phosphatase of prostatic origin with the Du Pont ACA is reported. Th affinity of the enzyme towards certain substrates, and the specificity of sodium thymolphthalein monophosphate as a substrate for prostatic acid phosphatase were investigated. The validity of this method, which is supposed to be specific for prostatic phosphatase is, however, limited; clinical data showed that related human acid phosphatase interfere and decrease the specificity of the determination.