Kuklenyik Zsuzsanna, Needham Larry L, Calafat Antonia M
Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
Anal Chem. 2005 Sep 15;77(18):6085-91. doi: 10.1021/ac050671l.
We have developed an on-line solid-phase extraction (SPE) method coupled to high-performance liquid chromatography (HPLC)-tandem mass spectrometry (MS/MS) for measuring trace levels of 18 perfluorinated chemicals (3 perfluorosulfonates, 8 perfluorocarboxylates, 7 perfluorosulfonamides) in serum. Without protein precipitation, only dilution with 0.1 M formic acid, one aliquot of 100 microL of serum was injected into a commercial column switching system that allowed for concurrent SPE and HPLC-MS/MS acquisition. First, the analytes were concentrated on a C18 SPE column. Then, this column was placed automatically in front of a C8 analytic HPLC column for chromatographic separation of the analytes. Detection and quantification were done using negative-ion TurboIonSpray ionization, a variant of electrospray ionization, MS/MS. Excellent recovery was achieved for all analytes including the volatile sulfonamide derivatives that could not be determined before using traditional off-line SPE methods. The high throughput and low limits of detection (0.05-0.8 ng/mL) using a small sample volume (100 microL of serum) and isotope dilution quantification make this method suitable for large-scale epidemiologic studies.
我们开发了一种在线固相萃取（SPE）与高效液相色谱（HPLC）-串联质谱（MS/MS）联用的方法，用于测定血清中痕量的18种全氟化合物（3种全氟磺酸盐、8种全氟羧酸盐、7种全氟磺酰胺）。无需进行蛋白质沉淀，仅用0.1 M甲酸稀释后，取100 μL血清注入商用柱切换系统，该系统可同时进行固相萃取和HPLC-MS/MS分析。首先，分析物在C18固相萃取柱上富集。然后，该柱自动置于C8分析型HPLC柱前，对分析物进行色谱分离。采用负离子TurboIonSpray电离（电喷雾电离的一种变体）进行MS/MS检测和定量。对于所有分析物，包括使用传统离线固相萃取方法之前无法测定的挥发性磺酰胺衍生物，均实现了出色的回收率。该方法通量高、检测限低（0.05 - 0.8 ng/mL），使用小样本量（100 μL血清）且采用同位素稀释定量，适用于大规模流行病学研究。
