An amperometric sensor for uric acid based on ordered mesoporous carbon-modified pyrolytic graphite electrode

A novel amperometric sensor for uric acid based on ordered mesoporous carbon modified pyrolytic graphite electrode was developed. Uric acid oxidation was easily catalyzed by this electrode in a phosphate buffer solution at pH 7.0, with an anodic potential decrease about 140 mV compared to bare pyrolytic graphite electrode. The uric acid level was determined by the amperometric method, at a constant potential of 0.31 mV, the catalytic current of uric acid vs. its concentration showed a good linearity in the range of 1.0 x 10(-6)-1.0 x 10(-4) mol L-1, with a correlation coefficient of 0.999. The detection limit was 4.0 x 10(-7) mol L-1. The proposed method could be effectively used for uric acid amperometric sensing in human urine.