Enzyme electrode probes obtained by electropolymerization of monomers with PMS and selected dehydrogenase enzymes

摘要

5-methylphenazonium methylsulphate, (commonly named phenazine methosulphate, PMS) mediated electroxida-[li0n of fl-nicotinamide adenine dinucleotide (phosphate), reduced form, (NAD(P)H), on platinum, gold and carbon electrodes has been studied by electropolymerization of 1,2-, 1,3-, l,,4-diaminobenzene (DAB), pyrrole-2-carboxylic acid (PY-2-COOH) and 4,4'-dihydroxybenzophenone (DHB) in presence of PMS using cyclic voltammetry. The I eletroxidation, of ascorbic acid has been evaluated On the electrodes elctropolymerized in absence and in presence of MS. The same experiments have been carried out with NAD(P)H in solution. Results showed that the NAD(P)H is oxidized by PMS coimmobilized with the polymer film on the electrode surface. NAD(P)H has been measured in range 10↑(-6) 10↑(-2) mol 1↑(-1) with a detection limit of 5× 10↑(-7) mol 1↑(-1). Amperometric measurements of NAD(P)H ave been carried out at -0.10 V and the efficiency of different electrodes based on different materials has been studied. The electropolymerization has been also carried out in presence of PMS and selected dehydrogenase enzymes. The activity of these enzymes has been tested amperometrically at - 0.1 V. Enzyme substrates such as glucose, lactate and glutamate have been measured in the range 5 × I0↑ (-6)-1×10↑(-↑) mol 1↑(-1) with a detection limit I × 10↑(-6) mol 1↑(-1). AIso the stability of these probes during time has been evaluated. #1997 Published by Elsevier Science B.V.