An on-line solid phase extraction-liquid chromatography-tandem mass spectrometry method for the determination of perfluoroalkyl acids in drinking and surface waters

An uhplc-ms/ms multiresidue method based on an on-line solid phase extraction (spe) procedure was developed for the simultaneous determination of 9 perfluorinated carboxylates (from 4 to 12 carbon atoms) and 3 perfluorinated sulphonates (from 4 to 8 carbon atoms). this work proposes using an on-line solid phase extraction before chromatographic separation and analysis to replace traditional methods of off-line spe before direct injection to lc-ms/ms. manual sample preparation was reduced to sample centrifugation and acidification,thus eliminating several procedural errors and significantly reducing time-consuming and costs. ionization suppression between target perfluorinated analytes and their coeluting sil-is were detected for homologues with a number of carbon atoms less than 9,but the quantitation was not affected. total matrix effect corrected by sil-is,inclusive of extraction efficacy,and of ionization efficiency,ranged between -34 and +39%. the percentage of recoveries,between 76 and 134%,calculated in different matrices (tap water and rivers impacted by different pollutions) was generally satisfactory. lods and loqs of this on-line spe method,which also incorporate recovery losses,ranged from 0.2 to 5.0 ng/l and from 1 to 20 ng/l,respectively. validated on-line spe-lc/ms/ms method has been applied in a wide survey for the determination of perfluoroalkyl acids in italian surface and ground waters. © 2015 michela mazzoni et al.