State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Guangzhou Institute of Quality Monitoring and Inspection, Guangzhou 510110, China.
J Chromatogr A. 2014 May 9;1341:50-6. doi: 10.1016/j.chroma.2014.03.032. Epub 2014 Mar 16.
Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are two perfluorinated compounds (PFCs) ubiquitously present in the environment, which could pose potential adverse effects on human health. Contamination and presence of PFOA and PFOS should be eliminated or rigidly restricted in food stuffs such as cooking oils and lard (from pig adipose tissue). This work describes a rapid, simple, reliable and sensitive method for quantitative analysis of PFOA and PFOS in cooking oils and pig adipose tissue with liquid chromatography tandem mass spectrometry (LC-MS/MS). The pretreatment mainly included a one-step reversed-phase liquid-liquid extraction using the mixture of basified water/methanol as the aqueous system, and dichloromethane (DCM) as the non-polar system. PFOA and PFOS can be successfully separated from the two lipid-rich matrices, i.e., cooking oil and adipose tissue, and extracted into the aqueous system, and then directly analyzed with LC-MS/MS. This method was validated in terms of accuracy (both intra- and inter-batch), precision, recovery, linearity, sensitivity and applicability. The intra-batch accuracies for PFOA and PFOS in cooking oil samples were within 93.9-101.9% with relative standard deviation (RSD) no more than 10.9%, and the inter-batch accuracies were 91.2-96.2% with RSD not exceeding 10.0%. The intra-batch accuracies of the analytes in pig adipose tissue samples were 102.9-113.0% with RSD of 8.8-13.1%. And the quantification ranges of PFOA and PFOS were 0.01-25ng/mL. This method has been applied to the analysis of PFOA and PFOS in real samples collected from local markets in Guangzhou, China.
全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）是两种普遍存在于环境中的全氟化合物（PFCs），它们可能对人类健康造成潜在的不良影响。在食用油和猪油（来自猪脂肪组织）等食品中，应消除或严格限制 PFOA 和 PFOS 的污染和存在。本工作描述了一种快速、简单、可靠和灵敏的液相色谱串联质谱法（LC-MS/MS）定量分析食用油和猪脂肪组织中 PFOA 和 PFOS 的方法。预处理主要包括一步反相液-液萃取，以碱性水/甲醇混合物作为水相，二氯甲烷（DCM）作为非极性相。PFOA 和 PFOS 可以成功地从两种富含脂质的基质，即食用油和脂肪组织中分离出来，并提取到水相中，然后直接用 LC-MS/MS 进行分析。该方法在准确性（批内和批间）、精密度、回收率、线性、灵敏度和适用性方面进行了验证。在食用油样品中，PFOA 和 PFOS 的批内准确度在 93.9-101.9%之间，相对标准偏差（RSD）不超过 10.9%，批间准确度在 91.2-96.2%之间，RSD 不超过 10.0%。在猪脂肪组织样品中，分析物的批内准确度为 102.9-113.0%，RSD 为 8.8-13.1%。PFOA 和 PFOS 的定量范围为 0.01-25ng/mL。该方法已应用于分析从中国广州当地市场采集的真实样品中的 PFOA 和 PFOS。
