流动注射-微柱在线富集/电感耦合等离子发射光谱法测定中成药中痕量铅和镉

Determination of Trace Lead and Cadmium in Traditional Chinese Medicine by Flow Injection-on-Line Preconcentration-Inductively Coupled Plasma Optical Emission Spectrometry

采用自制固相萃取材料PTFE-g-GMA-PEI纤维填充微柱预富集和流动注射(FI)与电感耦合等离子发射光谱仪联用,测定样品中痕量Pb2+和Cd2+。对Pb2+和Cd2+的富集与洗脱条件进行优化,并给出相应离子的分析特性。结果表明:本方法Pb2+和Cd2+检出限分别为3.5和0.15μg/L;富集倍数分别为30和80;RSD分别为1.5%和0.6%(n=9,单个离子浓度为50μg/L)。本方法应用于几种中成药中的痕量铅和镉的同时测定,样品加标回收率在90%～108%之间,结果满意。

Using a micro-column packed with polyethylenimine aminated glycidyl methacrylate-grafted-polytet-rafluoroethylene fiber made by ourselves as the adsorption material, the adsorption behaviors of Pb and Cd under different conditions were studied by inductively coupled plasma optical emission spectrometry. The conditions for the preconcentration of Pb and Cd such as pH, flow-rate, time and eluent acidity were optimized. The results show that the PTFE-g-GMA-PEI Fiber has excellent adsorption property and high adsorption capacity for Pb^2＋ and Cd^2＋. The Enrichment factors for Pb^2＋ and Cd^2＋ were 30 and 80, respectively and the detection limits were 3.5μg/L and 0.15μg/L, respectively, the relative standard derivations were 1.5% and 0.6% （ n = 9 ） respectively. When the single ion concentration was 50μg/L, the sampling frequency was 9 and 18 times/h, respectively. The method was applied to the simultaneous determination of trace lead and cadmium of several Chinese traditional medicine samples, the standard recovery of samples was 90%-108%.