Square wave voltammetric sensing of uric acid using the self-assembly of mercaptobenzimidazole

Abstract

The self-assembled monolayer of a heterocyclic thiol, mercaptobenzimidazole (MBI) on gold (Au) electrode is successfully utilized for the voltammetric sensing of uric acid (UA). The self-assembly of MBI separates the voltammetric signal of UA from the interfering ascorbate (AA). Selective detection of UA in the presence of a large excess of AA or the simultaneous detection of UA and AA is achieved at the MBI monolayer-modified electrode. This electrode can detect as low as 1 microM of UA in the presence of 100-fold excess of AA with excellent reproducibility. The practical utility of the electrode is demonstrated by measuring the concentration of UA in human serum.