Electrochemical exfoliated graphene oxide nanosheets modified graphite electrode for clozapine sensing

Graphene oxide nanosheets (GONs) are ideally suited for implementation in electrochemical applications due to their large electrical conductivity, large surface area and low production costs. In this research, electrochemical exfoliated graphene oxide-modified graphite electrode was developed for voltammetric determination of clozapine (CLZ). The dependence of oxidation peak current on the pH of the solution, scan rate and concentration of analyte were studied to optimize the experimental conditions for electrochemical determination of CLZ. The experimental results suggested that the modified electrode promoted electron transfer reaction for the oxidation of CLZ. The modified electrode exhibited high effective surface area, more reactive sites and excellent electrocatalytic activity toward the oxidation of CLZ. In the concentration range of 0.75–100 µM of CLZ in citrate buffer solution (CBS, pH 6), the anodic peak currents, measured via differential pulse voltammetry (DPV), presented good linear relationship with limit of detection (LOD) of 2.15 nM and good sensitivity of 0.0477 µA µM−1. The proposed method was successfully applied to quantify the amount of CLZ in the blood serum and plasma of schizophrenia patient.