Electrochemical Sensor Based on Ferric Oxide/ Reduced Graphene Oxide Nanocomposite for Linezolid Determination

Abstract

An innovative electrochemical sensor, constructed on a ferric oxide-reduced graphene oxide (Fe2O3/RGO) nanocomposite-modified carbon paste electrode, was developed for the determination of linezolid (LNZ) in pharmaceutical formulations. LZN is a critically important oxazolidinone antibiotic widely used to treat severe infections caused by multidrug-resistant Gram-positive pathogens. Owing to its narrow therapeutic index and the risk of dose-related adverse effects during prolonged therapy, sensitive and reliable analytical methods for its determination are essential to support quality control and therapeutic drug monitoring. The morphology and electrochemical behavior of the fabricated Fe2O3/RGO nanocomposite were evaluated. Cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical behavior of LNZ at the modified electrode. Optimal analytical performance was accomplished systematically by adjusting different DPV experimental parameters. Under the optimized conditions, a linear response was revealed over the concentration range of 0.4–7.0 µM, with a limit of detection of 0.152 µM and a limit of quantification of 0.461 µM was exhibited by the sensor. This method was successfully employed to the quantification of LNZ in pharmaceutical dosage forms, producing accurate and reproducible results. The developed sensor establishes high sensitivity, good repeatability, and satisfactory analytical performance, confirming its suitability for routine pharmaceutical analysis.