气相色谱-负化学电离源质谱法测定鱼油中16种多氯联苯

Determination of 16 polychlorinated biphenyls in fish oil by gas chromatography-negative ion chemical ionization-mass spectrometry

建立了气相色谱-负化学电离源质谱（GC-NCI-MS）同时测定鱼油中16种多氯联苯（PCBs）的方法。鱼油样品经正己烷提取和浓硫酸净化,在选择离子监测模式下进行GC-NCI-MS检测。所检测的PCBs在0.01～10μg/L范围内呈现良好的线性关系（r〉0.99）,定量限（S/N=10）在3～67 pg/g之间。基质加标回收率为62.3%～121.8%,相对标准偏差（n=3）≤12%。相比传统的多种填料固相萃取前处理法,本方法样品处理简单快速,有机溶剂使用量少,具有较好的抗基质干扰能力和较高的灵敏度,适用于鱼油中痕量共平面多氯联苯及常见指示性多氯联苯等的同时检测。

An analytical method for the simultaneous determination of 16 polychlorinated biphenyls （PCBs） in fish oil was developed. PCBs were extracted from fish oil with n-hexane, purified by sulfuric acid and determined by using gas chromatography-negative ion chemical ionization-mass spectrometry （GC-NCI-MS） in selected ion-monitoring （SIM） mode. A good linear relationship （r〉0.99） was observed with the PCBs concentrations from 0.01μg/L to 10 μg/L, and the limits of quantification （LOQ, S/N= 10） were between 3 pg/g and 67 pg/g for different kinds of PCBs. The average recoveries ranged from 62.3% to 121.8% with the relative standard deviations （RSDs, n--3） smaller than 12%. Compared with the traditional pre-treat- ment of multiple material solid phase extraction, this new method is simple, rapid and less organic solvent usage. Meanwhile the method has good selectivity and sensitivity, and it is suit- able for the determination of multiple trace PCBs in fish oil.