毛细管电泳间接检测法分析树叶中的重金属离子

Heavy Metal Ions in Leaves by Capillary Electrophoresis with Indirect Detection

采用弱络合剂乙醇酸,间接检测毛细管区带电泳法(CZE)对重金属离子Ba^(2+),Cr^(3+),Cd^(2+),Pb^(2+),Ni^(2+)进行了分离研究.通过对背景电解质种类和浓度、弱络合剂的浓度、缓冲液pH、微波消解条件等的优化,确定了以12mmol/L乙醇酸-10mmol/L吡啶(pH=3.8)为电泳缓冲液,采用压力进样方式,在10kV恒压下对树叶中的重金属离子进行分离,并在波长255nm处检测.5种重金属离子标样在1.0~30.0mg/L呈良好线性关系,3个水平的加标回收率为93.5%~100.6%.

Capillary zone electrophoresis with on-column complexation using glycolic acid,indirect UV detection was applied to the separation of Ba^2＋,Cr^3＋,Cd^2＋,Pb^2＋and Ni ^2＋from leaves.The influence of carrier electrolyte＇s kind and concentration,glycolic acid concentration and pH,as well as conditions of microwave assisted digestion,were investigated and discussed.The heavy metal ions were separated in a 12mmol/L glycolic acid-10mmol/L pyridine（pH=3.8）buffer,applied voltage of 10 kV and detection wavelength of 255 nm.Under the optimum conditions,the calibration curves of five heavy metal ions were linear in the range of concentrations 0.1-30mg/L.The recovery of the method was 93.5%-100.6%.