Development of a headspace solid-phase microextraction method combined with gas chromatography mass spectrometry for the determination of phthalate esters in cow milk
Development of a headspace solid-phase microextraction method combined with gas chromatography mass spectrometry for the determination of phthalate esters in cow milk
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DOI：
10.1016/j.aca.2005.02.020
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发表时间：
2005-05-04
影响因子：
6.2
通讯作者：
Sensenstein, R
中科院分区：
文献类型：
--
作者：
Feng, YL;Zhu, JP;Sensenstein, R
在奶牛场挤奶过程中，从增塑聚氯乙烯（PVC）管释放到生牛奶中的邻苯二甲酸酯可能是乳制品中邻苯二甲酸酯污染的潜在来源。采用顶空固相微萃取（HS-SPME）技术开发了一种测定原料牛奶样品中这些邻苯二甲酸酯的方法。将牛奶样品与氯化钠混合，并在90 ℃下提取60分钟。SPME纤维上收集的邻苯二甲酸酯然后在GC进样口解吸，然后在单离子监测（SIM）模式下进行GC-MS分析。SPME纤维的提取效率取决于牛奶样品中的脂肪含量。由于每种牛奶样品中的脂肪含量不同，因此采用标准加入和内标法相结合的方法对牛奶样品中的邻苯二甲酸酯进行定量。除邻苯二甲酸二甲酯外，两个加标水平的回收率均超过90%。对于含有高达10.8%脂肪的样品，邻苯二甲酸二（2-乙基己基）酯（DEHP）的方法检测限为0.31至3.3 ng g（-1）。该方法灵敏度足以检测两组原料牛奶样品（使用和不使用PVC管采集的牛奶样品）中的邻苯二甲酸二（2-乙基己基）酯、邻苯二甲酸二丁酯（DBP）和邻苯二甲酸二乙酯（DEP）。虽然DBP和DEP在两种类型的样本中发现了相似的水平，但使用PVC管收集的样本中DEHP的水平（215.36 ng g（-1））远高于不使用PVC管收集的样本（16.04 ng g（-1）），表明DEHP可能从PVC管中浸出到生牛奶中。(c)2005 Elsevier B. V.保留所有权利。
Phthalate esters released from plasticized polyvinyl chloride (PVC) tubing into raw cow milk during milking at dairy farms could be a potential source of contamination by phthalate esters in dairy products. A method was developed for the determination of these phthalate esters in raw cow milk samples using a headspace solid-phase microextraction (HS-SPME) technique. The milk samples were mixed with sodium chloride and extracted for 60 min at 90 degrees C. The phthalates collected on the SPME fibre were then desorbed in the GC injection port followed by GC-MS analysis in single ion monitoring (SIM) mode. The extraction efficiency of the SPME fibre was dependent on the fat content in the milk sample. Since the fat content in each cow milk sample was different, a combined standard addition and internal standard method was used for the quantification of the phthalate esters in milk samples. The recoveries at two spiking levels were over 90% except for dimethyl phthalate. The method detection limit for di-(2-ethylhexyl) phthalate (DEHP) was from 0.31 to 3.3 ng g(-1) for samples containing up to 10.8% fat. This method was sufficiently sensitive to detect di-(2-ethylhexyl) phthalate, dibutyl phthalate (DBP) and diethyl phthalate (DEP) in two groups of raw cow milk samples (cow milk samples collected using and without using PVC tubing). While similar levels were found in both types of samples for DBP and DEP, the level of DEHP was much higher in samples collected using PVC tubing (215.36 ng g(-1)) than once without (16.04 ng g(-1)), indicating potential leaching of DEHP from PVC tubing into raw cow milk. (c) 2005 Elsevier B.V. All rights reserved.