Exploring an indirect quantification strategy for PFOA in rat tissues via efficient degradation and fluorescence spectroscopy

Perfluorooctanoic acid (PFOA) has aroused global attention due to its persistence, biotoxicity and bioaccumulative properties. Monitoring PFOA levels in biological samples could give significant insights into its toxicity mechanism and health risk evaluation. Herein, to explore the distribution of PFOA in biological tissues, an indirect quantitation strategy for PFOA in biological samples was proposed based on fluorescence spectroscopy. F - ion was produced through highly efficient degradation of PFOA in polar aprotic solvent, and then F - ion was detected with highly selective F - ion fluorescent probe, which enabled the indirect quantitative detection of PFOA in biological samples. The sensitivity for PFOA was exhibited with limit of detection of 3.55 μM. The method’s accuracy and precision were validated by spiked biological sample experiment, with recovery rate ranging from 93.2 % to 105.5 % and relative standard deviation below 9.2 %. The content of PFOA was successfully detected in rats livers, kidneys and lungs tissues. Density function theory was employed to explore defluorination pathway, indicating that heating, alkaline and water conditions played a crucial role in the degradation of PFOA to produce F - ion. Thus, this novel strategy is suitable for quantitative analysis of PFOA in biological samples with high selectivity, sensitivity, recovery ratio, and simple sample preparation, which also provides a strategy for evaluating the levels of per- and polyfluoroalkyl substances in biological samples.