同位素稀释的气相色谱-质谱法测定食品模拟物中邻苯二甲酸酯类增塑剂

目的建立同位素稀释法测定4种食品模拟物中18种邻苯二甲酸酯(PAEs)类增塑剂的方法。方法水模拟物、3%(W/V)乙酸模拟物和20%乙醇模拟物中的18种增塑剂用正己烷萃取,95%乙醇模拟物加水稀释至20%乙醇后,再用正己烷萃取,采用GC-MS进行分析,同位素稀释法定性定量。结果 18种PAEs经内标校正后的线性R2≥0.9991;线性范围DINP和DIDP为0.2~5.0 mg/L,DMEP、DEEP和DBEP为0.02~2.0 mg/L,其他13种化合物的线性范围为0.005~2.0 mg/L;18种PAEs的内标相对回收率85.3%~115.0%,DIDP和DINP的定量限为200.0μg/L,其余16种PAEs的定量限为0.1~6.7μg/L,RSD≤10%。结论与以往的国标方法相比,该方法扩大了邻苯二甲酸酯类的检测范围,解决了高醇模拟物的检测结果不稳定的问题,采用同位素稀释法定性定量,结果更准确,方法更简单、可靠。

Determination of phthalic acid esters plasticizer in food simulants by gas chromatography-mass spectrometry isotope dilution method

Objective The isotope dilution method for determination of 18 phthalic acid esters( PAEs) plasticizer in four kinds of food simulants were developed. Methods18 PAEs were extracted by hexane in water,3%( W / V) acetic acid and 20% ethanol of food stmulant. The 95% ethanol of food simulant was diluted to 20% ethanol by water and then was extracted by hexane. Results The linear range of DINP and DIDP were 0. 2-5. 0 mg / L meanwhile the DMEP,DEEP and DBEP were 0. 02- 2. 0 mg / L,the other 13 PAEs were 0. 005- 2. 0 mg / L,the relative coefficients were greater more than 0. 9991 by internal standard calibration. The limit of detection of16 PAEs were 0. 1- 6. 7 μg / L,DIDP and DINP were 200. 0 μg / L. The average recoveries were from 85. 3% to 115. 0%with RSD less than 10%. Conclusions Compared with the previous national standard method,the detection series of phthalic acid esters were expanded. The stability of the test results were solved in simulant 95% ethanol. The method is simple and repeatable by isotope dilution statutory quantitatively.