Study On The Method For Determination Of Methyl Tert-butyl Ether And Its Metabolite In Serum

Objective：The purpose of the present study was to set a high sensitivity、good repeatability、low cost、simple and time-saving method for simultaneous determination of methyl tert-butylether (MTBE) and tert-butyl alcohol (TBA) in human serum, and provide technical methods fordetection of MTBE and TBA in serum. Through the detection for serum samples from somepeople, build up the headspace solid-phase microextraction and gas chromatography-massspectrometry method for MTBE and TBA in serum.The method meet the demands of Guide forEstablishing Occupational Health Standards.Method: The headspace solid-phase microextraction and gas chromatography-massspectrometry method with quadrupole mass spectrometers was used to extract and separateMTBE and TBA from the serum sample for qualitative and quantitative analysis. The bestdetermination conditions of headspace solid-phase microextraction and gas chromatography-mass spectrometry were tested and chosen, and then the methodology performance of each indexsuch as linear range、the limit of detection、accuracy、the relative standard deviation weredetermined and studied for the established method.113samples from MTBE-occupationalexposed population and99samples from non-occupational exposed population were verifiedthrough this method.Results：The regression equations of standard curves of the MTBE with Y=909.6X-529.2andTBA with Y=307.72X-79.154(r=0.9996and r=0.9996). For MTBE, the calibrationconcentration range from0.75μg/Lto40μg/L. For TBA, the calibration concentration range from1μg/L~1000μg/L. The limit of detection were0.23μg/L and0.27μg/L for MTBE and TBAseparately. In verified experiment, the regression equations of standard curves of the MTBE withY=1326.3X-26.903and TBA with Y=542.78X-121.55(r=0.9996、r=0.9999). For MTBE, thecalibration concentration range from0.1μg/L to20μg/L. For TBA, the calibration concentrationrange from0.1μg/L~20μg/L.The limit of detection were0.03μg/L for MTBE and0.05μg/L forTBA.The results showed that, for MTBE and TBA, the mean recovery percentages range atthree levels of concentration were78.7%~85.8%and75.8%~82.8%. The relative standarddeviation (RSD) which expressed the precision for intra-day and inter-day were MTBE：6.19%~7.46%and7.32%~8.76%，TBA：3.01%~5.97%and5.92%~7.85%. The serum samples were stable for at least28days when stored at-20℃with a biodegradation <10%.Outcome from the verification by crowd found that the concentration rang of occupationalexposed cluster of MTBE and TBA were2.18μg/L~16.30μg/L and26.45μg/L~2145.30μg/L, themedian concentration for MTBE and TBA were6.04μg/L and137.48μg/L while the meanconcentration for MTBE and TBA is6.23μg/L and224.15μg/L separately. The concentrationrang of non-occupational exposed cluster of MTBE and TBA were0.07μg/L~1.25μg/L (exceptfor the samples that were below the limit of detection) and10.78μg/L~188.54μg/L, the medianconcentration for MTBE and TBA were0.22μg/L and78.43μg/L while the mean concentrationwere0.29μg/Land81.63μg/L.Conclusion：The headspace solid-phase microextraction gas chromatography-mass apectrometrymethod was established in serum, the field application indicates that method was simple and easyof use with good precision and accuracy for determination of MTBE and TBA. And it can meetthe requirements of various indexes of determination methods of biological materials in ourcountry.