Biocompatible laponite ionogels based non-enzymatic oxalic acid sensor

Abstract

An enzyme-free oxalic acid (OA) electrochemical sensor was assembled on indium tin oxide (ITO) plate on which a film of laponite ionogel was coated that resulted in an L/IL/ITO electrode. This ionogel electrode was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and UV–Vis spectroscopy techniques. Electrochemical oxidation of OA on the electrode surface was investigated by cyclic voltammetry. Further this electrode exhibited high electrochemical activity that yielded well-defined peaks of OA oxidation, and a notably suppressed over-potential compared to the laponite–ITO (L/ITO) electrode. Under optimized conditions, a good linear response (anodic current) was observed for the OA concentration in the 1–20 mM range with a detection limit of 3 μM. Furthermore, this electrochemical strip sensor presented good characteristics in terms of stability, and reproducibility offering promise of applicability of this green sensor platform. Keywords: Ionogels, Enzyme-free, Oxalic acid, Biosensor, Cyclic voltammetry