Tracking Perfluorooctanoic Acid in Tap and River Water Employing Screen-Printed Electrodes Modified with Molecularly Imprinted Polymers

While existing polyfluoroalkyl substances (PFAS) detection techniques are highly sensitive, their broader implementation is limited by the need for expensive equipment, lengthy analysis times, and specialized personnel. This underscores the need for fast, reliable, cost-effective, and accessible PFAS detection methods to avoid exposure to these pollutants and expedite the remediation of contaminated environments. Currently, portable electrochemical sensors for <i>in situ</i> contaminant detection are gaining significant attention. This study focuses on developing an electrochemical sensor for on-site perfluorooctanoic acid (PFOA) detection utilizing screen-printed electrodes (SPEs) modified with molecularly imprinted polymers (MIPs). The sensor's performance is evaluated using electrochemical impedance spectroscopy (EIS), with the electrochemical signals for PFOA detection arising from the specific interactions between MIPs and PFOA. The sensor exhibits a linear response to PFOA in phosphate-buffered saline within a concentration range of 0.1 nM to 10 μM, a detection limit of 19 ± 1 pM, and a quantification limit of 42 ± 3 nM. The selectivity of the sensor is assessed by measuring its response to four different PFAS compounds. Additionally, its real-world applicability is tested by analyzing the EIS response in tap and river water samples. The developed sensor, which combines an easy-to-use dipstick format with readily prepared SPEs, has the potential for large-scale production for <i>in situ</i> PFOA detection.