PYRUVATE AND LACTATE ELECTROCHEMICAL SENSORS REALIZED WITH IMMOBILIZED ENZYMES FOR CONTROL IN ARTIFICIAL PANCREAS

Lactate and pyruvate sensors have been realized by immobilizing lactate oxidase and pyruvate oxidase both obtained form Pediococcus on polymeric membranes and fixing them on hydrogen peroxide electrochemical sensors. Cellulose acetate membranes with molecular cutoff of 100 was used to eliminate interference from ascorbic acid, glutathione etc. Lactate sensor was very stable and precise in any conditions while for pyruvate the presence of several cofactors in solutions was necessary to enhance sensitivity due to its lower concentration in blood. The sensors were coupled with an artificial pancreas for monitoring in vivo in human diabetic patients the fate of lactate, pyruvate other than glucose with the purpose of better dosage of insulin or any other drugs.