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

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5~1000 μ g/L,检出限为0.3~1.1 μ g/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6.0~142.7 μ g/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。

Determination of phthalate monoesters and diesters in urine by solid-phase extraction and gas chromatography-mass spectrometry

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 derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide before GC-MS analysis. Good linear relationships were obtained in the range of 5-1000 μ g/L. The limits of detection were between 0.3 and 1.1 μ g/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 μ g/L. The method is highly accurate, reliable and sensitive for monitoring phthalate monoesters and diesters in urine.