Determination of Organophosphate Esters in Human Serum Using Gel Permeation Chromatograph and Solid Phase Extraction Coupled with Gas Chromatography-Mass Spectrometry

A gel permeation chromatograph (GPC) coupled with solid phase extraction and gas chromatography-mass spectrometric (GPC-SPE-GC/MS) method was developed to analyze seven kinds of organophosphate esters, including Tri-n-butylphosphate, Tri(2-chloroethyl)phosphate, Triphenyl phosphate, Tris(2-butoxyethyl) phosphate, Tri-o-tolylphosphate, Tri-m-tolylphosphate and Tri-p-tolylphosphate in human serum. The recoveries of cleanup methods between GPC-silica/alumina column and H2SO4-silica/sulfuric acid gel column were compared. The purification method with the GPC-silica/alumina column didn't destroy the structure of organophosphate esters (OPEs) and could effectively remove some proteins and lipid matrix influence in serum. The developed method was verified using the spiked blank and the spiked serum, and the good recoveries and reproducibilities were achieved. The recoveries of all of OPEs in spiked blank (n = 3) were all more than 75%. The recoveries of d12-TCEP and d15-TPhP in human serum samples (n = 9) were 86.3% ± 21.6% and 103.1% ± 16.5%, respectively. In human serum samples (n = 9), the detection ratios for TnBP, TCEP, TPhP, TBEP and m-TTP were more than 90% in all of the serum samples, p-TTP was only 30%, and o-TTP was not detectable. The concentrations of TnBP, TCEP, TPhP, TBEP and m-TTP in serum were 3.4–46.5 ng g−1 lipid, 248.6–958.2 ng g−1 lipid, < 4.2 ng g−1 lipid, < 49.9 ng g−1 lipid and < 23.1 ng g−1 lipid, respectively.

Graphical abstractA gel permeation chromatography coupled with solid phase extraction and gas chromatography-mass spectrometric (GPC-SPE-GC/MS) method was developed to analyze seven kinds of organophosphate esters in human serum. The good recoveries and reproducibility were achieved under the optimized conditions of extraction and purification.Figure optionsDownload full-size imageDownload as PowerPoint slide