Development of a solid phase microextraction-gas chromatography–mass spectrometry method for the determination of pentachlorophenol in human plasma using experimental design

A new method, headspace solid-phase microextraction (HS-SPME) with in situ derivatization and gas chromatography–mass spectrometry (GC–MS), which was used for the determination of trace amount of pentachlorophenol (PCP) in human plasma was presented. The acetylation derivatization reaction was firstly optimized using a Doehlert design. Then a series of parameters relevant to the headspace SPME procedure, including fiber coating, extraction temperature, extraction time and salt addition, were optimized using a two-level full factorial design expanded further to a central composite design. The validation of method showed that the optimized method had good linearity (R2 = 0.999) within the concentration ranges 0.1–50.0 ng ml−1, and was sensitive with the limit of detection of 0.02 ng ml−1. Intra- and inter-day precision for pentachlorophenol in human plasma samples were not greater than 11.9% and 12.6%, respectively. The proposed method, to our knowledge, describes the first application of HS-SPME with GC–MS for analysis of PCP in blood plasma sample. Application of the method to real human plasma samples, PCP was successfully detected in some cases at concentration levels 1.2–6.3 ng ml−1.