固相萃取-气相色谱-质谱法分析尿液中邻苯二甲酸单酯和双酯

摘要

A method for the determination of phthalate monoesters and diesters in urine by solid-phase extraction and gas chromatography-mass spectrometry ( SPE-GC-MS ) was developed. After urine enzymatic hydrolysis by β-glucuronidase,the sample was pretreated by SPE. Phthalate monoesters and diesters were eluted by acetonitrile,ethyl acetate and ethyl ester-n-hexane(1:19,v/v),separately. The mixture of the elution was dried by N2 and deri-vatized with N,O-bis( trimethylsilyl)trifluoroacetamide before GC-MS analysis. Good linear rela-tionships were obtained in the range of 5-1 000 μg/L. The limits of detection were between 0. 3 and 1. 1 μg/L. The recoveries of phthalate monoesters and diesters were in the range of 77. 9%-97. 7% and the relative standard deviations ( RSDs ) were 3. 7% -10. 9%. The method was applied to analyze 50 urine samples. Seven compounds, such as di-2-ethylhexyl phthalate ( DEHP),were detected. The mean concentrations were between 6. 0 and 142. 7 μg/L. The method is highly accurate,reliable and sensitive for monitoring phthalate monoesters and dies-ters in urine.%建立了固相萃取-气相色谱-质谱测定尿液中邻苯二甲酸单酯和双酯的分析方法。尿液经β-葡萄糖苷酸酶酶解后进行固相萃取净化，用乙腈、乙酸乙酯和乙醚-正己烷（1：19，v／v）分别洗脱，合并洗脱液，氮气吹干后，用 N，O-双三甲基硅基三氟乙酰胺（ BSTFA）对邻苯二甲酸单酯进行硅烷化处理，使用气相色谱-质谱法检测。邻苯二甲酸单酯和双酯的线性范围为5~1000μg／L，检出限为0.3~1.1μg／L，回收率为77.9％~97.7％，相对标准偏差为3.7％~10.9％。应用该方法对50份尿液进行检测，检出邻苯二甲酸二（2-乙基己基）酯（DEHP）等7种邻苯二甲酸单酯和双酯类物质，平均质量浓度为6.0~142.7μg／L。该方法准确、可靠、灵敏度高，适用于尿液中邻苯二甲酸单酯和双酯的同时测定。