A novel ultra thin polydivinylbenzene/ethylvinylbenzene composite membrane has been developed for use as the outer covering barrier in a model amperometric glucose oxidase enzyme electrode. The composite membrane was formed via the cathodic electropolymerization of divinylbenzene/ethylvinylbenzene at the surface of gold sputter coated host alumina membranes, (serving solely as a mechanical support for the thin polymer film). Permeability coefficients were determined for the enzyme substrates, O 2 and glucose, across composite membranes formed with a range of polymer thicknesses. Due to the highly substrate diffusion limiting nature of the composite membrane, it was found that anionic interferents present in blood (such as ascorbate), were effectively screened from the working electrode via a charge exclusion mechanism, in a manner similar to previous findings within our laboratory. The enzyme electrode showed an initial 32% signal drift when first exposed to whole human blood over a period of 2 hours, after which time enzyme electrode responses remained essentially stable. Whole blood patient glucose determinations yielded a correlation coefficient of r 2 ¼ 0.97 in comparison to standard hospital analyses.

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An ultrathin composite membrane has been developed as the outer covering barrier in a model amperometric lactate oxidase enzyme electrode. The membrane was formed by cathodic electropolymerization of divinylbenzene/ ethylvinylbenzene at the surface of a gold coated polyester support membrane. Permeability coefficients were determined for O 2 and lactate across membranes with a range of polymer thicknesses. Anionic interferents (such as ascorbate) were screened from the working electrode by the composite membrane. The composite enzyme electrode showed an increased working concentration range and extended linearity of responses in comparison to an uncoated enzyme electrode.

An ultrathin composite membrane has been developed as the outer covering barrier in a model amperometric glucose oxidase enzyme electrode. The membrane was formed by cathodic electropolymerization of divinylbenzene/ ethylvinylbenzene at the surface of a gold coated polyester support membrane. Permeability coefficients were determined for O 2 and glucose across membranes with a range of polymer thicknesses. Anionic interferents (such as ascorbate), were screened from the working electrode via a charge exclusion mechanism. The enzyme electrode showed an initial 10% signal drift when first exposed to whole human blood over a period of 2 hours, after which responses remained essentially stable. Whole blood patient glucose determinations yielded a correlation coefficient of r 2 ¼ 0.99 compared to standard hospital analyses.

A simple commercial polyester polymer membrane has been found to exhibit an intense electrochromic effect. Most polymers which undergo electrochromic effects contain either transition metals or extensive conjugated systems. We have found that a simple commercial polyester membrane when coated with gold and polarised to-4 V (vs. Ag) in aprotic organic solvents displays an electrochromic colour change from a colourless to an intense red state.