Manganese Oxide as an Electrochemical Sensor for Carbamazepine and Sulfamethoxazole in Wastewater Samples

Abstract

The extensive use of pharmaceutical compounds poses a growing threat to environmental and public health. Carbamazepine (CBZ) and sulfamethoxazole (SMX), widely used in veterinary and human medicine, are persistent pollutants often detected in water bodies. Their presence at trace levels can contribute to the development of antibiotic resistance. In this study, a novel electrochemical sensor based on manganese oxide nanoparticles (MnO2NPs) modified screen-printed carbon electrode (SPCE) was fabricated for the detection of CBZ and SMX. The effects of pH, scan rate, and analyte concentration were systematically investigated. Under optimized conditions, the sensor exhibited excellent sensitivity with detection limits of 0.106 nanomolar (CBZ) and 0.082 nanomolar (SMX), respectively within a linear range of 0.97–5.82 nanomolar. The sensor showed outstanding selectivity and stability, and its effectiveness was confirmed by recovery tests in real wastewater samples, with values ranging from 95% to 110% (CBZ) and 90% to 105% (SMX), respectively. These findings demonstrate the practical potential of MnO2NPs/SPCE-based sensors for monitoring emerging contaminants.