建立了动物源性食品中硫柳汞残留量的LC-AFS分析方法.样品经酸、碱提取液提取,液相色谱分离后,先与氧化剂混合,再与空气混合,通过紫外光照射,硫柳汞被氧化成无机汞,最后与还原剂和盐酸发生氢化反应,进入原子化器,进行原子荧光测定.对样品前处理条件、液相色谱条件、氧化剂和原子荧光工作条件进行了考察.在优化实验条件下,硫柳汞在0～20μg/L范围内线性关系良好,相关系数为0.9994,检出限为(S/N=3)0.4μg/L.5种样品在10.0、20.0、40.0μg/kg 3个加标水平下的平均回收率为71%～83%,相对标准偏差(RSD)为1.6%～4.5%.该法适用于动物源性食品中硫柳汞残留量的测定.%A LC - AFS method was developed for the determination of thimerosal residues in foods of animal origin. The analyte in sample was extracted with the acidic and basic extraction solutions,and separated by liquid chromatography. Thimerosal was mixed with oxidizing reagent and air, then exposed to UV light, and oxidized to inorganic mercury. After hydride generation reaction, the atomized mercury could be determined by atomic fluorescence spectrometry (AFS). Sample preparation, mobile phase, oxidizing reagent and operating conditions of AFS were optimized. Under the optimal conditions, the calibration curve for thimerosal was linear over the concentration range of 020 μg/L with a correlation coefficient of 0. 999 4. The detection limit was 0. 4 μg/L. The average recoveries of thimerosal from five samples spiked at three levels of 10. 0, 20. 0, 40. 0 μg/kg were in the range of 71％ -83％ with RSDs of 1.6％ -4. 5％. The method was suitable for the determination of thimerosal residues in foods of animal origin.
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