硅烷化衍生／气相色谱／电子捕获检测水产品中羟基多氯联苯的研究

Study on Determination of Hydroxy-polychlorinated Biphenyls in Fishery Products by Silylation Derivatization/GC/μECD

以贻贝为实验样品,采用正己烷-乙酸乙酯(体积比1:1)为萃取溶剂,超声提取,硫酸、活性硅胶柱净化去除脂质及蛋白干扰物质,以双(三甲基硅烷基)三氟乙酰胺-三甲基氯硅烷(BSTFA-TMCS,体积比99:1)为衍生试剂对羟基多氯联苯进行硅烷化衍生,确定了最佳衍生参数,并研究了气相色谱/电子捕获检测水产品中羟基多氯联苯的分析条件。研究得出,硅烷化衍生最佳衍生温度为60℃,最佳衍生时间为40min;阴性空白贻贝样品在1、2、4μg/kg的添加水平下,3-OH-PCB101、4-OH-PCB112、4-OH-PCB106的平均回收率为72%～84%,RSD为0.4%～10.6%,检出限为1.0μg/kg。该方法可用于水产品中羟基多氯联苯的检测。

A method for the determination of three hydroxy-polychlorinated biphenyls （hydroxy - PCBs） in fishery products was proposed by gas chromatography with electron capture detection（ GC/ μECD）, and the negative muscle tissue was used to verify the veracity in qualitative and quantitative analysis of the method. The target compounds were extracted by ultrasonic-assisted technique using hexane and ethyl acetate as extracting solvents. The impurities were removed by sulfuric acid and sili- ca column with 50 mL hexane -ethyl acetate（ 1 ： 1, by volume） as eluent. N, O-bis（trimethylsi- lyl） -trimethylchlorosilane（ BSTFA- TMCS, 99 ： 1 ） was used as derivative reagent. The optimal conditions were using 100 μL derivatizing agent reacting at 60 ℃ for 40 min. The average recoveries of 3-OH-PCB101, 4-OH-PCB112 and 4-OH-PCBI06 from muscle sample spiked at three levels of 1, 2, 4 μg/kg standard ranged from 72% to 84%. The relative standard deviations （RSDs） were 0. 4% - 10.6% with a detection limit of 1.0 μg/kg. The method could be applied in the determina- tion of hydroxy-polychlorinated biphenyl in fishery products.