Enhanced sensitivity and selectivity of an electrochemical sensor for real-time propofol monitoring in anesthesia
Yang Gao, Yaning Guo, He Ping, Zhijie Liu, Yongxue Chen
Abstract
In this study, an electrochemical sensor for the real-time monitoring of propofol (PPF) in anesthesia was developed using molecularly imprinted polymers and reduced graphene oxide-modified glassy carbon electrodes (MIPs/rGO/GCE). To make the electrode, GO was thermally reduced into rGO, which was then electrodeposited on GCE (rGO/GCE), followed by the electropolymerization of MIPs using LiClO4, pyrrole, and PPF (template) solution on rGO/GCE (MIPs/rGO/GCE). The PPF was then taken out of the pyrrole polymer. X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and X-ray Photoelectron Spectroscopy (XPS) examinations of surface composition and morphology revealed that electropolymerization MIP on rGO/GCE and reduction and deposition of rGO on GCE were both successful processes. MIPs/rGO/GCE revealed significant sensitivity and selectivity towards PPF in electrochemical tests utilizing cyclic voltammetry (CV) and amperometry. Results demonstrated a linear range from 0.5 to 250 μM that was steady and wide, with a sensitivity of 1.0776 μA/μM and a detection limit value of 0.08 μM. MIPs/rGO/GCE demonstrated outstanding electrocatalytic activity over a broad linear range and a reasonable detection limit value for PPF concentrations. To assess the method's applicability for the analysis of PPF, it was applied to real biological samples of human plasma and urine.