Packed-Nanofiber solid phase extraction coupled with gas chromatography-mass spectrometry for the determination of phthalate esters in urines from children

In this paper, we developed a rapid and safe method based on packed-fiber solid-phase extraction (PFSPE) system coupled with gas chromatography-mass spectrometry for the determination of four phthalate esters (PAEs), diethyl-o-phthalate (DEP), dibutyl-o-phthalate (DBP), di (2-ethylhexyl) phathalate (DEHP), di-n-octyl phthalate (DNOP), in urine samples. The PAEs in urine samples (500μL) were rapidly cleaned up from urines using polystyrene (PS) nanofibers packed micro-columns fitted on a PFSPE pretreatment device, which can process up to 12 samples simultaneously in 5min. Under optimum conditions, satisfied recovery and relative standard deviation values (RSDs) were in the range of 80.4-111.7% and 1.5-10.9%, respectively. The limits of detection (LOD) and the limits of quantification (LOQ) were ranged from 0.1 to 0.5ngmL^-1 and 0.5-2ngmL^-1, respectively. The well controlled matrix effect was also evaluated by comparing the signal response of the pure PAEs standards dissolved in methanol with the signal response of PAEs in the urine matrix. This new method was successfully applied to determine four PAEs in urine samples of overweight and normal-weight children, and an association between phthalates in urines and obesity was observed. Thus, the method seems to be a useful tool for monitoring of the level of urinary phthalate esters and also to support an evidence for further reasearch of obesity.