Optimization Of The Method Of Determining Three Types Of Environmental Endocrine Disruptors In A Small Volume Human Serum By Gas Chromatography-mass Spectrometry

Polybrominated diphenyl ethers?PBDEs?,phthalate esters?PAEs?and bisphenol A?BPA?are three typical environmental endocrine disruptors?EEDs?,which are closely related to polycystic ovary syndrome?PCOS?.Serum samples with clinical background data are characterized by small volumes,precious materials,complex matrix,and low contaminant content,which increased the difficulty of quantitative analysis of EEDs.Based on the previous research,a method was developed to determine three types of EEDs?PBDEs,PAEs and BPA?in a small volume of serum simultaneously by gas chromatogram-mass spectrometry?GC-MS?.This study reduced the background interference of PAEs by optimizing experimental procedures and details,experimental reagents and materials.The EEDs were extracted from the serum by vortex for three times using 10,5,and 5 mL ether.BDE-77,BDE-181,MBDE-208,and ¹³C₁₂-BPA were used as the recovery surrogates of tri-BDE to penta-BDE,hexa-BDE to hepta-BDE,deca-BDE,PAEs and BPA,respectively.In addition,acidic silica gel was used to improve the recovery of PBDEs components.For the obtention of the three components,concentrated hydrochloric acid?HCl?was added to destroy the protein structure of human serum samples,vortex extraction using ether was performed and purification on silica gel column was applied.Before determined by GC-MS,the internal standards were added.The calibration curves of PBDEs,PAEs and BPA showed a good linear relationship and the correlation coefficient?r?was greater than 0.99.In serum spiked experiments,the recoveries of the recovery surrogates of PBDEs,PAEs,and BPA were50.5%-124.6%,48.4%-90.6%,68.6%-84.8%,respectively,with their relative standard deviations?RSDs?3.1%-14.6%,0.9%-12%,and 8.1-19.6%,respectively.Moreover,the limits of detection?LODs?of PBDEs,PAEs,and BPA were 0.02-0.05 ng/mL,0.94-1.91 ng/mL,and0.15 ng/mL,respectively.21 human serum samples were determined by the established method.The results showed that the levels of PBDEs,PAEs and BPA were 1.62-97.34 ng/g,6.31-17.99 ng/mL and 1.07-9.16ng/mL,respectively after deducting background values.The method is sensitivity,accuracy,reproducibility,and can be used to determine trace PBDEs,PAEs and BPA in small volume human serum samples.