Electroactive poly(amino acids). Part 3. Ferrocene-doped poly(L-Iysine) as an electroactive layer on platinum

Abstract

Poly(L-lysine) hydrobromide in water was coated onto a platinum electrode and then doped with ferrocene residues by reaction with ferrocenecarbonyl chloride in benzene containing pyridine. The behaviour of this coating to cyclic voltammetry in acetonitrile was examined. There is no evidence of the ageing phenomenon previously reported for poly(N^ε;-4-nitrobenzoyl-L-Iysine) films. In the unchanged state, ferrocene residues are associated. In the oxidised state, the ferrociniurn residues appear evenly distributed through the film. Reduction of the oxidised state yields a film in which the ferrocene residues are evenly distributed but which relaxes within a few minutes to the state where ferrocene residues are associated. Charging can be repeated a large number of times with no deterioration in response.