Zirconium dioxide-decorated MWCNTs (ZrO2@MWCNTs) nanocomposite as a high-performance electrochemical sensing platform for psychotropic drug analysis

Abstract

Psychotropic medications are widely prescribed for the treatment and management of various psychiatric disorders. However, several of these medications, including carbamazepine (CBZ) and quetiapine (QTP), are associated with significant risks of drug–drug interactions and exhibit narrow therapeutic indices. Consequently, the rapid, sensitive, and selective detection of CBZ and QTP is of critical importance for accurate therapeutic drug monitoring, mitigation of adverse interactions, and optimization of clinical outcomes in psychiatric care. In this regard, a highly sensitive and selective electrochemical sensing platform was developed for the determination of CBZ and QTP based on electrodes modified with zirconium oxide nanoparticle/multi-walled carbon nanotube nanocomposites (ZrO₂@MWCNTs). The electrochemical behaviors of both target analytes were comprehensively characterized using cyclic voltammetry (CV), linear sweep voltammetry (LSV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The nanocomposite-modified electrodes exhibited pronounced electrocatalytic activity toward the oxidation of CBZ and QTP, as evidenced by a substantial enhancement in the oxidation peak currents and a marked decrease in their redox potentials. Under optimized experimental conditions, the proposed sensing system demonstrated outstanding analytical performance, achieving limits of detection of 0.01 µM and 0.025 µM for CBZ and QTP, respectively, along with wide linear dynamic ranges spanning 0.05–4022 µM for CBZ and 0.08–4022 µM for QTP. Moreover, the platform displayed excellent selectivity, reproducibility, and reliability and was successfully applied to the quantification of CBZ and QTP in commercial pharmaceutical formulations. The developed ZrO₂@MWCNTs-based electrochemical sensing platform represents a rapid, cost-effective, and efficient approach for psychotropic drug monitoring, with considerable potential for future implementation in pharmaceutical analysis and point-of-care testing (POCT) applications.