Method development for analysis of short- and long-chain perfluorinated acids in solid matrices
In order to help to elucidate the transport and fate of perfluorinated acids (PFAs) in the environment, a reliable and sensitive analytical method has been developed in present study for determination of short- and long-chain PFAs in various solid matrices. The method consisted of solvent extraction of PFAs from solid matrices using sonication, solid phase extraction (SPE) using weak anion exchange (WAX) cartridges, clean-up of SPE eluent with dispersive carbon sorbent and quantitation by high performance liquid chromatography-negative electrospray-tandem mass spectrometry (HPLC-negative ESI-MS/MS). The method detection limits (MDL) and quantitation limits (MQL), which were analyte- and sample-dependent, ranged from 0.02 to 0.06 ng g−1 and 0.10 to 0.90 ng g−1, respectively. The recoveries of all PFAs were generally good enough for quantitative analysis of these chemicals (57−115%), especially for short-chain (<C8, 80−115%) PFAs excluded in previous studies because methods were not available. The precisions of this method, represented by the percent relative standard deviation (RSD) of spiked measurements, were in a range of 1−19%. In addition, matrix effect did not affect analyte quantification in solid matrices in most cases, and the validated method was successfully applied to analyses of short- and long-chain PFAs in various solid matrices.