在2 mL尿液样品中加入4 mg·L^-1混合内标溶液0.01 mL、不低于850 U·mL^-1的β-葡萄糖醛酸酶溶液和1 mol·L^-1乙酸铵溶液0.5 mL,充分振荡后于37℃水解2.0 h,降至室温,用乙腈定容至5 mL,冷冻2 h,恢复至常温后,过0.22 μm有机滤膜。采用高效液相色谱-串联质谱法同时测定其中12种邻苯二甲酸酯类代谢物的含量,基质匹配法消除基质干扰,内标法定量。结果表明,12种邻苯二甲酸酯类代谢物工作曲线的线性范围均为1.00~200 μg·L^-1,检出限(3S/N)为0.05~1.88 μg·L^-1。按标准加入法进行回收试验,回收率为75.3%~114%,测定值的相对标准偏差(n=6)为1.5%~10%。方法用于测定35份儿童尿液样品,其中检出11种邻苯二甲酸酯类代谢物,邻苯二甲酸单异癸酯(MDP)未检出。

The mixed internal standard solution (4 mg·L^-1, 0.01 mL), β-glucuronidase solution not less than 850 U·mL^-1 and 0.5 mL of 1 mol·L^-1 ammonium acetate solution were added into 2 mL of the urine sample. After shaking fully, the mixture was hydrolyzed at 37℃ for 2.0 h. After cooling to the room temperature, the volume of the solution was made up to 5 mL with acetonitrile. The solution was froze for 2 h, warmed to the room temperature, and filtered through 0.22 μm organic filter membrane. The 12 metabolites of phthalates in the above solution were determined by high performance liquid chromatography-tandem mass spectrometry, using matrix matching method to eliminate the matrix interference, and internal standard method to quantify. As shown by the results, the linear ranges of working curves of 12 metabolites of phthalates were all 1.00-200 μg·L^-1, with detection limits (3S/N) in the range of 0.05-1.88 μg·L^-1. Test for recovery was made by standard addition method, giving results in the range of 75.3%-114%, with RSDs (n=6) of the determined values in the range of 1.5%-10%. This method was applied to determination of 35 children urine samples, of which 11 metabolites of phthalates were detected, and monoisodecyl phthalate (MDP) was not detected.