混合无机酸消解-固相萃取-高效液相色谱-串联质谱法分析贝类壳体中的3种全氟磺酸化合物

Determination of three perfluoro sulfonated chemicals in bivalve shells using high performance liquid chromatography-tandem mass spectrometry with the pretreatment of mixed inorganic acid digestion coupled with solid-phase extraction

建立了采用混合无机酸消解-固相萃取(SPE)-高效液相色谱-电喷雾电离串联质谱(HPLC-ESI-MS/MS)分析贝类壳体中的3种全氟磺酸化合物的方法。将贝壳粉经硝酸/盐酸混合酸消解,用氢氧化钠调节消解液的pH值至6后采用OasisWAX固相萃取柱富集净化,然后采用内标法通过HPLC-ESI-MS/MS在分时段选择反应监测模式下分析上述全氟磺酸化合物。结果表明,该方法对于贝壳中全氟丁烷磺酸、全氟己烷磺酸和全氟辛烷磺酸的检出限(LOD)分别为0.28,0.42和0.43ng/g,加标回收率为94.88%～96.24%。采用此方法对渤海湾两种双壳贝类壳体进行的采样分析也表明,贝壳中3种目标污染物的含量范围为<LOD～0.70ng/g,比其在贝类软组织中的含量低约1个数量级。实验结果表明混合酸消解-SPE提取是检测贝类壳体中此类污染物的有效前处理方法。

For the analysis of perfluorobutane sulfonate （PFBS）,perfluorohexane sulfonate （PFHxS） and perfluorooctane sulfonate （PFOS） in shells,an extraction method of mixed inorganic acid digestion coupled with solid phase extraction （SPE） was established. The target compounds were determined by high performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS）. The shell powder was at first digested with the mixture of nitric acid and hydrochloric acid,then the digestion solution was adjusted to pH 6 with sodium hydroxide,and cleaned up with Oasis WAX SPE cartridge. The perfluoro sulfonated chemicals were quantified with HPLC-MS/MS using electrospray ionization in negative ion mode with internal standard method. The limits of detection （LODs） were of 0.28 ng/g for PFBS,0.42 ng/g for PFHxS and 0.43 ng/g for PFOS,and matrix recoveries of the perfluoro sulfonated chemicals were 94.88%-96.24%. The analytical results for the shells of two bivalves from Bohai Bay showed this pretreatment method is suitable for the determination of perfluoro sulfonated acids （PFSAs） in shells. Concentrations of PFSAs in the shells ranged from LOD-0.70 ng/g,which were an order of magnitude lower than those in the soft tissues of these bivalves.