One step fabrication of nanoelectrode ensembles formed via amphiphilic block copolymers self-assembly and selective voltammetric detection of uric acid in the presence of high ascorbic acid content.

A novel one-step approach to glassy carbon nanoelectrode ensembles (NEEs) with the pores of 20-120nm in radii has been developed using an amphiphilic block copolymer [polystyrene-block-poly (acrylic acid)] self-assembly. This procedure is simple and fast, and requires only conventional, inexpensive electrochemical instrumentation. Electrochemical methods were used to characterize the NEEs prepared using this new procedure. The NEEs drastically suppressed the response of ascorbic acid (AA) and resolved the overlapping voltammetric response of uric acid (UA) and AA into two well-defined peaks with a large anodic peak difference (DeltaE(pa)) of about 310mV. The peak current obtained from differential pulse voltammetry (DPV) was linearly dependent on the UA concentration in the range of 0.25-50microM at neutral pH (PBS, pH 6.86) with a correlation coefficient of 0.999, and the detection limit was 0.04microM (S/N=3). The NEEs has also been demonstrated to be applicable in the detection of UA in serum and urine samples with excellent sensitivity and selectivity. The NEEs will hopefully be of good application for further sensor development.