Determination of acid phosphatase activity in a double injection flow system with electrochemical detection Original Research Article

An enzyme assay for the measurement of total and prostatic acid phosphatase activity by flow injection analysis with electrochemical detection has been developed. The substrate (α-naphthyl phosphate) and enzyme are simultaneously injected to the system by means of a double injection valve. The α-naphtol produced after stopping the flow is amperometrically quantified. The calibration curve is linear from 0.01 to 1.3 u/l with a limit of detection of 0.006 u/l. Results were compared with that obtained spectrophotometrically.