Polyacrylamide-Based Redox Polymer for Connecting Redox Centers of Enzymes toElectrodes

摘要

Enzyme electrodes based on complexing a water-soluble copolymer of acrylamide andvinylimidazole with OS(dmebpy)2C1+/2+ (dmebpy = 4,4'-dimethyl,2,2'-bipyridine) and crosslinking with oxidases by water-soluble crosslinkers are described. The potential of the polyacrylamide based redox polymer is +55mV (SCE), a typical electron diffusion coefficient (De) in the redox hydrogel that results of its crosslinking is 1.3-O.1 x 10 to the 9th power sq cm/s. The properties of the enzyme electrodes formed when this redox hydrogel 'wired' horseradish peroxidase (HRP), lactate oxidase (LOX) or glucose oxidase (GOX), depended on the thickness of the hydrogel film, the chemistry of their crosslinking and their enzyme content. At the wired HRP electrodes, H2O2 was electrocatalytically reduced to water at O.OV (SCE). Lactate and glucose were electrocatalytically oxidized at 0.16 V, (SCE). The GOX electrodes, when made with a 140 microg/sq cm thick gels were selective for glucose in the presence of physiological concentrations of urate and ascorbate. jg.