利用铽与钙调素的荧光熄灭作用测定精锌中镉  

Determination of Trace Cadmium with Terbium Ion and Calmodulin by Fluorescence Quenching Method

作　　者：肖凤娟[1] 常虹[2] 张希清[1] 

机构地区：[1]石家庄铁道学院材料科学与工程分院,河北石家庄050043 [2]河北师范大学物理学学院,河北石家庄050016

出　　处：《稀土》2005年第4期42-45,共4页Chinese Rare Earths

基　　金：河北省科技厅科技攻关项目(023204)

摘　　要：研究了Cd2+对铽离子与钙调素(CaM)所形成的配合物(Tb34+·CaM)的荧光熄灭作用,考察了常见金属离子的干扰情况,在pH=5.0的六次亚甲基四胺缓冲溶液中,不断通入N 2作保护气体可防止O 2对Tb34+·CaM荧光的熄灭作用.由此建立了测定Cd2+的新方法,Cd2+浓度在0.0723～15.80μg/mL范围内与荧光熄灭值△IF具有良好的线性关系,检测下限为0.044μg/mL,相对标准偏差为5.1%.用该方法测定了精锌中镉的含量,平均回收率为96.1%.Fluorescence quenching effect of TM^3＋ 4·CaM system produced by Cd^2＋ was investigated . The results show that the degree of quenching is linear with the concentration of Cd^2＋ in the range of 0. 0723-15.80μg/mL . This method can be applied to the determination of trace cadmium with detection limit 0. 044μg/mL , relative standard deviation 5.1%. It has been applied to the determination of Cd in fine zinc ore with the recoveries of 96.1%.

关 键 词：铽离子 钙调素 荧光熄灭 镉 

分 类 号：O657.31[理学—分析化学]