Development of eco-friendly and cost-effective electrochemical sensor for the simultaneous detection of 4-aminophenol and paracetamol in water

Pharmaceutical waste contamination is an increasing environmental concern due to its persistence and potential adverse impact on aquatic ecosystems. Among these contaminants, paracetamol (PA) and 4-aminophenol (4-AP) are prevalent in urban wastewater due to their widespread use. Accurate detection of these compounds is essential for environmental risk assessment and mitigation strategies. In this study, an electrochemical sensor based on carbon screen-printed electrodes (C-SPEs) modified with functionalized carbon nanofibers (CNF-COOH) was developed for the simultaneous detection of PA and 4-AP. The electrochemical performance of commercially available gold and carbon-based SPEs was evaluated, demonstrating superior sensitivity for PA and 4-AP with C-SPEs. The incorporation of CNF-COOH improved electron transfer and increased surface area, enhancing both sensitivity and selectivity by facilitating stronger interactions with the target analytes. The novel C-SPE/CNF-COOH sensor achieved detection limits of 0.002 mM for PA and 0.007 mM for 4-AP. It was successfully tested in real freshwater samples, demonstrating high accuracy even in complex matrices. This innovative methodology provides a rapid, cost-effective, and portable analytical tool for routine monitoring of pharmaceutical contaminants, enabling more accurate environmental risk assessments and supporting the implementation of more efficient management strategies.