Yu Chang Ho, Patel Bhupendra, Palencia Marilou, Fan Zhihua Tina
Chemical Terrorism, Biomonitoring and Food Testing Program, Public Health & Environmental Laboratories, New Jersey Department of Health, Ewing, NJ 08628, United States of America.
Chemical Terrorism, Biomonitoring and Food Testing Program, Public Health & Environmental Laboratories, New Jersey Department of Health, Ewing, NJ 08628, United States of America.
J Chromatogr A. 2017 Jan 13;1480:1-10. doi: 10.1016/j.chroma.2016.11.063. Epub 2016 Dec 6.
A selective, sensitive, and accurate analytical method for the measurement of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in human serum, utilizing LC-MS/MS (liquid chromatography-tandem mass spectrometry), was developed and validated according to the Centers for Disease Control and Prevention (CDC) guidelines for biological sample analysis. Tests were conducted to determine the optimal analytical column, mobile phase composition and pH, gradient program, and cleaning procedure. The final analytical column selected for analysis was an extra densely bonded silica-packed reverse-phase column (Agilent XDB-C, 3.0×100mm, 3.5μm). Mobile phase A was an aqueous buffer solution containing 10mM ammonium acetate (pH=4.3). Mobile phase B was a mixture of methanol and acetonitrile (1:1, v/v). The gradient program was programmed by initiating a fast elution (%B, from 40 to 65%) between 1.0 and 1.5min, followed by a slow elution (%B: 65-80%) in the period of 1.5-7.5min. The cleanup procedures were augmented by cleaning with (1) various solvents (isopropyl alcohol, methanol, acetonitrile, and reverse osmosis-purified water); (2) extensive washing steps for the autosampler and solid phase extraction (SPE) cartridge; and (3) a post-analysis cleaning step for the whole system. Under the above conditions, the resolution and sensitivity were significantly improved. Twelve target PFASs were baseline-separated (2.5-7.0min) within a 10-min of acquisition time. The limits of detection (LODs) were 0.01ng/mL or lower for all of the target compounds, making this method 5 times more sensitive than previously published methods. The newly developed method was validated in the linear range of 0.01-50ng/mL, and the accuracy (recovery between 80 and 120%) and precision (RSD<20%) were acceptable at three spiked levels (0.25, 2.5, and 25ng/mL). The method development and validation results demonstrated that this method was precise, accurate, and robust, with high-throughput (∼10min per sample); thus suitable for large-scale epidemiological studies.
根据疾病控制与预防中心（CDC）生物样本分析指南，开发并验证了一种利用液相色谱 - 串联质谱法（LC-MS/MS）测定人血清中全氟烷基和多氟烷基物质（PFASs）的选择性、灵敏且准确的分析方法。进行了多项测试以确定最佳分析柱、流动相组成及pH值、梯度程序和清洗程序。最终选定用于分析的分析柱是一种超密键合硅胶填充反相柱（安捷伦XDB-C，3.0×100mm，3.5μm）。流动相A是含有10mM醋酸铵（pH = 4.3）的水性缓冲溶液。流动相B是甲醇和乙腈的混合物（1:1，v/v）。梯度程序设置为在1.0至1.5分钟之间启动快速洗脱（%B，从40%至65%），随后在1.5至7.5分钟期间进行缓慢洗脱（%B：65% - 80%）。清洗程序通过以下方式增强：（1）用各种溶剂（异丙醇、甲醇、乙腈和反渗透纯净水）清洗；（2）对自动进样器和固相萃取（SPE）小柱进行大量冲洗步骤；（3）对整个系统进行分析后清洗步骤。在上述条件下，分辨率和灵敏度显著提高。12种目标PFASs在10分钟的采集时间内实现了基线分离（2.5 - 7.0分钟）。所有目标化合物的检测限（LOD）均为0.01ng/mL或更低，使得该方法比先前发表的方法灵敏5倍。新开发的方法在0.01 - 50ng/mL的线性范围内得到验证，在三个加标水平（0.25、2.5和25ng/mL）下，准确度（回收率在80%至120%之间）和精密度（RSD<20%）均可接受。方法开发和验证结果表明，该方法精确、准确且稳健，具有高通量（每个样品约10分钟）；因此适用于大规模流行病学研究。
