Recent advances in the analysis of per- and polyfluoroalkyl substances (PFAS): A review

Per- and polyfluoroalkyl substances (PFAS), that are widely used in different industrial and commercial activities, have become emerging contaminants of concern. Thus, the evaluation of PFAS presence in diverse environmental matrices is of paramount importance, leading to the necessity in development of different types of analytical methods to analyse the trace amounts of PFAS with varying selectivity and sensitivity. Analytical methods that have been advanced and employed for PFAS identification are critically described with their strengths, limitations and future potentials in this review. This review includes, (i) instrument analytical methodologies, mainly focusing on sample preparation, extraction and recovery analysis, (ii) nanoparticle-based sensors, and an app-based smartphone portable sensor, for the monitoring and sensing of PFAS in different environmental matrices. Furthermore, (iii) total oxidisable precursor assay (TOPA), content of total organic fluorine (TOF) as well as total fluorine (TF) are also reviewed, which provide fundamental tools towards achieving precursor quantification and closing mass balance analysis.