Optimization of Solid Phase Extraction Method for Quantitative Analysis of Perfluorooctanoic Acid in Serum using Liquid Chromatography-Tandem Mass Spectrometry

A solid phase extraction (SPE) method was optimized for the quantitative analysis of perfluorooctanoic acid (PFOA)in serum using hydrophilic-lipophilic balance SPE and LC-MS/MS. Fetal bovine serums spiked with 13C8-PFOA before or afterSPE were used as test samples for evaluation of the SPE efficiency. Simultaneous evaluation of matrix effects and absolute SPErecovery for 13C8-PFOA in serum using different sample pre-treatments and SPE conditions allowed optimization of SPE processefficiency with minimal matrix effect and decent SPE recovery. Introduction of protein precipitation as a sample pre-treatmentprocedure for serum samples before SPE generally decreased matrix effect in LC-MS/MS analysis and provided morestable recovery of PFOA.