Ion Selective Electrodes for Phosphate Using Enzyme Systems

Abstract
Two different enzyme electrodes for the specific assay of phosphate ion are described. One system utilizes the enzymes phosphorylase-a, phosphoglucomutase and glucose-6-phosphate dehydrogenase, the second glyceraldehyde-phosphate dehydrogenase, phosphoglycerate kinase and hexokinase. In both cases the assay is effected by amperometric monitoring of the NADH or NADPH formed in the reaction at an applied potential of +0. 65 V.