AbstractThe construction and performance of new carbon paste enzyme electrodes as amperometric sensors is described. Xanthine oxidase and alkaline phosphatase have been adsorbed on a carbon paste electrode (CPE), and physically entrapped with a semipermeable membrane. The product of enzymatic reaction, uric acid or p‐nitrophenol, was electrochemically oxidized versus an Ag/AgCl electrode at +0.4 or +0.8 V, respectively, yielding a steady‐state current directly related to the substrate concentration. Response characteristics as well as kinetic parameters have been evalua