Cyclic voltammetric determination of capsaicin by using electrochemically deposited tin and reduced graphene oxide on screen-printed carbon electrodes

Abstract

Tin and reduced graphene oxide (Sn/rGO) was prepared by an electrochemical deposition and modified on a screen-printed carbon electrode (SPCE) in order to improve the electrode selectivity and sensitivity for determination of capsaicin in real samples. The modified electrode was characterized for its surface morphology by scanning electron microscopy (SEM). An elemental analysis of prepared catalysts was confirmed by energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS). The experimental conditions influencing determination of capsaicin were optimized. The experiment was carried out in a sodium acetate buffer solution pH 3.0 at a scan rate of 50 mV/s. The Sn/rGO/SPCE showed a linear working range of 0.2-22 µM of capsaicin concentrations. The limit of detection and limit of quantification were 0.005 µM (S/N=3) and 0.02 µM (S/N=10), respectively. The prepared electrode was successfully applied to determine capsaicin in real chili samples and chili sauces.