中药材地龙中七种指示性多氯联苯残留量测定研究

摘要

目的:建立动物源性中药材地龙中持久性有机污染物多氯联苯残留量的测定方法.方法:对样品提取方法中的提取溶剂、溶剂用量、提取时间进行正交试验,对两种净化方法(磺化-碱性氧化铝柱净化、GPC-碱性氧化铝柱净化)的净化效果进行比较,最终确定样品用正己烷-丙酮(1∶1)超声提取,提取液经磺化-碱性氧化铝柱净化,正己烷洗脱,氮吹浓缩后经气相色谱法测定,外标法定量.结果:7种指示性多氯联苯在0.002 ～7.0 mg ·L-1范围内线性关系良好,相关系数均大于0.9990,检出下限在0.006～0.025 mg·kg-1,定量下限在0.020～0.084 mg·kg-1,回收率在83.8％～ 105.3％,RSD在3.2％～7.5％.结论:本方法简便、快捷、灵敏度高、准确性好,适用于动物源性中药材中指示性多氯联苯残留量的测定.%Objective:To develop a method for the determination of residues of persistent organic pollutants polychlorobiphenyls (PCBs) in Pheretima derived from traditional Chinese medicine of animal origin.Methods:Orthogonal experimental design was carried out on the extraction solvent,dosage of solvent and extraction time in the sample extraction method.The purification effect of two kinds of purification methods:sulfonation-basic alumina column purification and GPC-basic alumina column purification were compared.The method was determined as follows:sample was extracted ultrasonically with n-hexane and acetone (1∶1),the extract obtained was purified by sulfonation-basic alumina column and eluted by n-hexane,the eluant was concentrated by nitrogen blowing instrument,and finally the concentrate was determined by gas chromatography and quantified by external standard method.Results:Good linearity was obtained when the concentration of 7 indicative polychlorobiphenyls were within 0.002-7.0 mg ·L-1,the correlation coefficients (r) were all greater than 0.999 0.The limit of detection and the limit of qualification were among 0.006-0.025 mg ·kg-1 and 0.020-0.084 mg ·kg-1,respectively.The recoveries were in the range of 83.8％-105.3％,with the relative standard deviation (RSD) among 3.2％-7.5％.Conclusion:This method is simple,rapid,sensitive and accurate,which is suitable for the determination of residues of indicative polychlorobiphenyls in traditional Chinese medicine of animal origin.