MULTIANALYTE SENSOR FOR THE SIMULTANEOUS DETERMINATION OF GLUCOSE, L-LACTATE AND URIC-ACID BASED ON A MICROELECTRODE ARRAY

In this work a microelectrode array was used to develop a multianalyte sensor. Glucose, L-lactate and uric acid were chosen as model analyte s. The array consists of ten groups of 40 microelectrodes connected in parallel, each of a size of 36 x 36 mu m. Thus the array showed a lar ge overall current response retaining typical microelectrode features. Single rows of electrodes were modified with enzymes entrapped in a p olymer matrix. As the three chosen oxidases were used as enzymes hydro gen peroxide generated by the enzymatic reaction was detected by anodi c oxidation at + 800 mV vs. Ag/AgCl/3 M KCl. The elimination of interf ering substances was accomplished by the application of a NAFION membr ane between the electrode surface and the enzyme layer. (C) 1997 Elsev ier Science S.A.