Molecularly Imprinted Polymer Functionalized on Reduced Graphene Oxide Electrochemical Sensor for Detection of Ciprofloxacin

Abstract

Ciprofloxacin (CIP) is widely utilised to treat bacterial infections. Currently, CIP is present in water sources at higher concentrations, thus necessitating close monitoring. This study developed electrochemical nano-sensors based on molecularly imprinted polymer (MIP) and reduced graphene oxide (rGO) composites to detect CIP. rGO served as the loading platform for MIP immobilisation on a glassy carbon electrode (GCE). A copolymer thin film, comprised of polyaniline copolymerized with o-phenylenediamine (PAni-co-PDA) was obtained by electro-polymerisation utilizing cyclic voltammetry (CV) under suitable conditions. The performance of the modified GCE was examined utilizing CV mode in a hexacyanoferrate electrolyte as an electrochemical probe. The PAni-co-PDA/rGO-modified GCE exhibited enhanced improvement and efficient electrocatalytic behaviour in the oxidation of CIP with relatively high sensitivity and stability. The sensor was operated in differential pulse voltammetry (DPV) mode. Our best results revealed good linearity response to CIP in the range of 0.001-10.0 μM with an R-squared of 0.949, a detection limit of 0.09 μM (3.3 SD/S), and the calibration plot of "I minus the logarithm of the CIP concentration exhibited a sensitivity of -1.521. The sensor demonstrated a conductive polymer-based device that can be utilised for rapid CIP determination in pharmaceutical samples and biological fluids.