Multilayer membranes via layer-by-layer deposition of ascorbate oxidase and Au nanoparticles on the Pt electrode for reduction of oxidation current derived from ascorbate

A glass plate was alternately immersed in an Au colloid (10 nm φ) and an ascorbate oxidase (AOx) solution (0.1 mg/mL, pH 6.8). Absorbance at 530 nm originating from the Au particles increased with the increasing number of depositions. The AOx activity of the plate also increased as the plate was immersed in the AOx solution. These results suggested that a multilayer membrane via the layer-by-layer deposition of AOx and Au nanoparticles was formed on the glass plate. AOx was also deposited on a Pt disk electrode using the same process. Using the (AOx/Au)10 modified electrode, the oxidation current of ascorbic acid (0.1 mM) decreased to 19% versus the unmodified electrode.