An ultra-sensitive molecularly imprinted polymer (MIP) and gold nanostars (AuNS) modified voltammetric sensor for facile detection of perfluorooctance sulfonate (PFOS) in drinking water

Perfluorooctance sulfonate (PFOS) is one of the most studied Per-and-polyfluoroalkyl substances (PFAS) due to its relatively high environmental ubiquity and toxicity. This study presented an ultra-sensitive voltammetric sensor for detection PFOS in tap water based on a glassy carbon electrode (GCE) modified with thin coating gold nanostar (AuNS) electropolymerized molecularly imprinted polymer (MIP). The AuNS helps enhance response blank signal intensity regarding Fe2+ oxidation selected ferrocenecarboxylic acid (FcCOOH) redox probe; meanwhile, statistical optimization MIP layer offers higher peak change. Analytical results indicated could detect LoD LoQ 0.015 0.041 nM (i.e., 7.5 20.5 ppt), respectively. Moreover, it showed comparable analytical performance U.S. Environmental Protection Agency (EPA) method Method 537.1). Interfering effects approximately 10% underestimation were observed when samples contained equimolar perfluorobutanoic Acid (PFBA) or perfluorobutanesulfonic (PFBS). Additionally, common interferents drinking sources, such as humic chloride ion, minor influence terms accuracy reproducibility.