Voltammetric Determination of Salbutamol, Sulfamethoxazole, and Trimethoprim as Anthropogenic Impact Indicators Using Commercial Screen-Printed Electrodes

A voltammetric method based on the use of screen-printed carbon electrodes (SPCEs) is presented for the simultaneous determination of salbutamol (SAL), sulfamethoxazole (SMX), and trimethoprim (TMP), with high sensitivity, fast response, and excellent repeatability and reproducibility. Under the optimal voltammetric conditions, the simultaneous analysis showed linear ranges of 0.3-2.5 mg L^-1, 0.3-11.1 mg L^-1, and 0.5-9.0 mg L^-1 for SAL, SMX, and TMP, respectively, and detection limits of 83.8 μg L^-1, 88.7 μg L^-1, and 139.2 μg L^-1, respectively. Additionally, the developed method was successfully validated by the analysis of a spiked river water sample with satisfactory recovery values in the range of 97.0-98.8%. The added value of the presented method relays in combining cost-effective disposable SPCEs with rapid analysis (<30 s), providing portable electrochemical tools for the on-site monitoring of pharmaceutical residues, which is critical for addressing contamination linked to anthropogenic activity.