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

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

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。

Objective The isotope dilution method for determination of 18 phthalic acid esters（PAEs） plasticizer in four kinds of food simulants were developed. Methods 18 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 O. 9991 by internal standard calibration. The limit of detection ofl6PAEs were 0. 1 -6.7 pog/L, DIDP and DINP were 200.0 p,g/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.