QuEChERS-气相色谱-质谱法测定不同食品基质中五氯酚及其钠盐残留量

QuECHERS-GC-MS Determination of Pentachlorophenol and Its Sodium Salt Residues in Different Food Matrices

[目的]采用QuEChERS前处理-气相色谱质谱(GC-MS)技术,建立不同食品基质中痕量五氯酚及其钠盐的快速检测方法。[方法]样品中加入超纯水涡旋均匀,加入1%(V/V)乙酸乙腈溶液与QuEChERS的盐包涡旋均匀,离心取上清液后,常温氮吹近干,经0.3 mol/L的碳酸钾混匀,乙酸酐衍生,正己烷涡旋萃取,DB-5MS色谱柱分离,GC-MS测定,外标法定量。[结果]五氯酚被衍生剂衍生成五氯苯乙酸酯,五氯酚浓度为1~50 ng/mL时,线性关系良好(R^(2)=0.99992),检出限为0.1μg/kg。在3种加标浓度下,空白基质五氯酚的加标回收率控制在90%~100%。[结论]该方法的灵敏度高、选择性好,定性、定量准确,适用于不同食品基质中五氯酚及其钠盐残留的检测要求。

[Objective]To establish a rapid detection method for trace amounts of pentachlorophenol and its sodium salt in different food matrices by using QuECHERS pretreatment-gas chromatography mass spectrometry(GC-MS)technology.[Method]Add ultrapure water to the sample and vortex uniformly,add 1%(V/V)acetic acid acetonitrile solution and QuECHERS salt packet to vortex uniformly.After centrifugation to take the supernatant,blow dry with nitrogen at room temperature.After mixing with 0.3 mol/L potassium carbonate,derivatize with acetic anhydride,vortex extraction with n-hexane,separate on DB-5MS column,determine by GC-MS,and quantify by external standard method.[Result]Pentachlorophenol was derivatized into pentachlorophenyl acetate by the derivatizing agent.When the concentration of pentachlorophenol was 1-50 ng/mL,the linear relationship was good(R^(2)=0.99992).The detection limit was 0.1μg/kg.At the three spiked concentrations,the spiked recovery rate of the blank matrix pentachlorophenol was controlled within 90% to 100%.[Conclusion]The method has high sensitivity,good selectivity,qualitative and quantitative accuracy,and it is suitable for the detection requirements of pentachlorophenol and its sodium salt residues in different food matrices.