Simultaneous determination of citalopram and selegiline using an efficient electrochemical sensor based on ZIF-8 decorated with RGO and g-C3N4 in real samples

A novel carbon paste electrode (CPE) modified with ZIF-8/g-C3N4/RGO nanocomposite is used as a high sensitive electrochemical sensor to simultaneously determine citalopram (CIT) and selegiline (SEL). Simultaneous determination of these drugs is important because of their effect on the level of neurotransmitter serotonin in the central nervous system (CNS) which can happen by overuse and concurrent consumption. Cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) are used in order to investigate the electrochemical behavior of the electrode. Various techniques such as scanning electron microscopy (SEM) with energy dispersive x-ray analysis (EDX), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) are employed to affirm the structure of ZIF-8/g-C3N4/RGO nanocomposite. Excellent sensing performance of the suggested electrode is verified based on the low limit of detection of 0.008 μM and 0.014 μM which represent two linear ranges from 0.009 to 900 μM for CIT and 0.09-900 μM for SEL, respectively. The analytical performance of the proposed electrochemical sensor is investigated in real samples including human blood and urine with acceptable results.