气相色谱-三重四级杆串联质谱法测定金枪鱼中的多氯联苯

Determination of PCBs in tuan by gas chromatography triple quadruples mass spectrometry

目的建立金枪鱼中7种指示性多氯联苯的三重四级杆气相色谱分析方法。方法金枪鱼采用经典的索氏提取法,以PCB198为定量内标,使用正己烷-二氯甲烷(1∶1,V/V)混合溶液作为提取溶液,提取液经浓缩后用固相萃取柱净化,经DB-5MS色谱柱程序升温分离,采用Acquisition-Timed方法,SRM扫描。结果 7种多氯联苯的质量浓度在10.0μg/L^400.0μg/L呈良好的线性关系,相关系数r为0.996 9~0.999 3,平均回收率为80.0%~114.0%,相对标准偏差(RSD)为1.98%~3.89%,方法检出限为0.02μg/kg^0.10μg/kg。结论本方法简单、快速、可靠,通过二级质谱扫描,减少了在复杂基质样品中的背景干扰,提高了目标化合物的检测灵敏度。

Objective To establish a method for the determination of 7 kinds of PCBs in tuna by Gas chromatography triple quadruples mass spectrometry. Methods Tuna samples were extracted by classic soxhlet method,PCB198 as quantitative internal standard,using solid phase extraction column purification after the concentration which was extracted with n- hexane-dichloromethane（ 1∶1,V / V）,and then separated by DB- 5MS capillary column and adopted the method of Acquisition-Timed,and scan SRM. Results The quantity and concentration of 7 kinds of polychlorinated biphenyls（ PCBs） showed good linear relation within 10. 0 μg / L- 400. 0 μg / L. The correlation coefficient（ r） was 0. 996 9- 0. 999 3,the average recovery of the method was 80. 0%- 114. 0%,and the relative standard deviation（ RSD） was 1. 98%- 3. 89%,the detection limit was0. 02 μg / kg- 0. 10 μg / kg. Conclusion The method was simple,rapid and reliable,which can improve the sensitivity of target compounds by secondary mass spectrum scanning through reducing the background interference in the complex matrix samples.