Glucose oxidase/hexokinase electrode for the determination of ATP

A hydrogen peroxide based enzyme electrode for the determination of ATP has been developed by the immobilization of glucose oxidase and hexokinase. Competition between the enzymes for the substrate glucose allowed the measurement of ATP. Different immobilization procedures and different types of hexokinase have been tested. Using a BSA-glutaraldehyde procedure and hexokinase from an overproducing strain of bakers' yeast, ATP was measured in the 0.05-0.5 mmol l(-1) range with a detection limit of 0.01 mmol l(-1). ATP concentrations comparable to those reported in the literature and a good recovery were obtained when the enzyme electrode was used with human erythrocyte hemolysate.