Electrocatalysis of NADH Oxidation with an Electropolymerized Film of 1,4-Bis(3,4-dihydroxyphenyl)-2,3-dimethylbutane

The oxidation of 1,4-bis(3,4-dihydroxyphenyl)-2,3-dimethylbutane, known also as nordihydroguaiaretic acid, on a glassy carbon electrode anodically pretreated in KCl solution gives rise to a stabile redox-active polymer containing the o-quinone moiety. The redox response of the modified electrode is typical for a surface-immobilized species. The modifier thickness can be easy controlled by a number of potential cycles applied during electropolymerization, and a surface coverage up to 1.1 x 10(-9) mol cm(-2) can be achieved. The film exhibits catalytic activity toward NADH oxidation. Characteristic kinetic constants for the mediated oxidation of NADH were derived from rotating disk experiments performed in phosphate or Tris/acetate buffers. The effects of film thickness, solution pH, and the presence of Mg2+ cation on the catalytic efficiency of the modified electrode were discussed and compared with literature data concerning related systems.