Phosphate-sensitive enzyme electrode: a potential sensor for environment control

A highly sensitive enzyme electrode was designed for the assay of phosphate ions. For this purpose, a bienzyme membrane with co-immobilized nucleoside phosphorylase and xanthine oxidase was used with a platinum amperometric electrode for the detection of enzymatically generated hydrogen peroxide. A detection limit of 10^?7 M was obtained and phosphate assays could be easily performed in the range 0.1–10 μM, which is of interest in the control of water pollution.