Development of a nickel hydroxide nanopetal decorated molecular imprinted polymer based electrode for sensitive detection of epigallocatechin-3-gallate in green tea

Abstract

Green tea possesses medicinal and therapeutic properties owing to the presence of a large number of catechins in it. Among them, epigallocatechin-3-gallate (EGCG) is the most significant and abundant catechin with a number of health promoting attributes. In this work, a molecularly imprinted polymer (MIP) is combined with Ni(OH)2 nanopetals to facilitate an efficient and selective detection of epigallocatechin-3-gallate (EGCG) in green tea. The Ni(OH)2 nanopetals synthesized using a simple solution route, was homogeneously mixed with the MIP prepared by the co-polymerization of acrylonitrile and ethylene glycol dimethacrylate along with graphite. Material characterizations were performed using powder X-ray diffraction (P-XRD), fourier transform infra-red (FTIR) spectroscope, UV-visible (UV-vis) spectroscope and field emission scanning electron microscope (FESEM), respectively. Considerable improvement in the electrochemical properties of the modified electrode was witnessed over the unmodified counterpart by means of cyclic voltammetry (CV). Differential pulse voltammetry (DPV) results depicted a linear range from 10 μM to 100 μM and limit of detection (LOD) as 7 nM which is eventually the lowest amongst reported literatures.. The electrode demonstrated reasonable analytical characteristics and its performance was also successfully validated with green tea samples using partial least square regression (PLSR) technique and standard addition method.