Determination of benzimidazole in biological model samples using electropolymerized-molecularly imprinted polypyrrole modified pencil graphite sensor

Molecularly imprinted polymer (MIP) of benzimidazole was prepared through electropolymerization and electrodeposition of pyrrole on a pencil graphite electrode in the presence of benzimidazole as template molecule. The ability of the fabricated MIP to act as a sensor of determining benzimidazole was investigated. Preparing of MIP and quantitative measurements were performed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), respectively. Several important parameters which controlling the performance of the polypyrrole and the method efficiency were investigated and optimized. The molecularly imprinted layer exhibited selectivity and sensitivity toward benzimidazole. The calibration curve demonstrated linearity over a concentration range of 3 x 10(-6) M to 5 x 10(-3) M with a correlation coefficient (r(2)) of 0.9920. The detection limit (based on S/N = 3) of benzimidazole was obtained 7.0 x 10(-7) M. The minimum and maximum recovery (%) through the spiking 2 mM benzimidazole to analyte free real biological matrices were obtained 85.1% (turkey) and 99.6% (chicken), respectively. A computational study based on density functional theory was performed to evaluate the template-monomer geometry and interaction energy in the prepolymerization mixture. (C) 2012 Elsevier B.V. All rights reserved.