Electrochemistry of glucose at gold nanoparticles modified graphite/SrPdO3 electrode – Towards a novel non-enzymatic glucose sensor

Abstract

An enzyme-free voltammetric glucose sensor based on gold nanoparticles modified graphite/SrPdO3 electrode is presented. The proposed glucose sensor showed prominent electrocatalytic activity toward the glucose oxidation in 0.1molL−1 NaOH. An effective synergism was achieved between the SrPdO3 perovskite and the gold nanoparticles film resulting in higher current response for glucose than the sum of the individual current values for SrPdO3 and gold nanoparticles. The nanocomposite provided plenty of active sites for the direct oxidation of glucose resulting in excellent performance in terms of highly reproducible response, high sensitivity, wide linearity and applicability in real urine samples and blood serum. The non-enzymatic glucose sensor exhibited good linear range in the concentration range from 100μmolL−1 to 6mmolL−1 with a detection limit of 10.1μmolL−1. Moreover, the interferences of ascorbic acid, uric acid, dopamine, paracetamol and chloride can be avoided at the proposed sensor presenting a highly selective non-enzymatic glucose sensor. In addition, the proposed sensor offered unique long term stability due to the intrinsic effects of the proposed nanocomposite.