Application of CO2-Plasma Treated Multilayer Graphene as an Electrochemical Sensing Platform for Paracetamol Monitoring

Abstract

Developing advanced materials is crucial for improving electrochemical sensing platforms, particularly by enhancing sensitivity, selectivity, and miniaturization. In this study, we introduce a CO2 plasma-treated multilayer graphene (MLG) paper as a novel electrode material for the electrochemical detection of paracetamol (PAR). A chemometric strategy based on design of experiments (DoE) was applied to efficiently optimize the parameters of the electroanalytical techniques employed for PAR detection. The electrode surface, characterized by scanning electron and atomic force microscopy, revealed a significant roughness and defect density, resulting in a larger electrochemically active surface area. The MLG electrodes were evaluated as voltammetric sensors using PAR as the target analyte, since it is relevant in pharmaceutical and environmental analysis. Electrochemical performance was assessed through cyclic voltammetry and square-wave adsorptive stripping voltammetry in various supporting electrolytes. The CO2 plasma-treated electrode (MLG-t) exhibited notably improved sensitivity toward PAR detection. The optimized sensor exhibited a linear working range of 0.30−8.4 µmol L−1 and a limit of detection of 0.080 µmol L−1. The analysis of the pharmaceutical tablets revealed recovery values in the range of 101.7% to 104.0%. These findings demonstrate that CO2 plasma treatment, coupled with DoE optimization, represents a valuable strategy for engineering cost-effective and high-performance graphene-based electrochemical sensors.