比色生物传感器检测Cd^(2+)  

Colorimetric biosensor for Cd^(2+) detection

作　　者：张婷婷[1] 张瑞英[1] 陈镇[1] 罗义庭 熊兴良[1] 

机构地区：[1]重庆医科大学生物医学工程研究室,重庆400016

出　　处：《传感器与微系统》2015年第5期143-145,共3页Transducer and Microsystem Technologies

基　　金：国家自然科学基金资助项目(30500125);重庆市自然科学基金资助项目(2008BB5395)

摘　　要：基于Cd2+—DNA复合物介导AuNPs聚集构建了比色生物传感器,并用于检测镉离子(Cd2+)。单链DNA(ssDNA)通过Au-N键与AuNPs静电吸附,带负电荷的DNA互相排斥,使DNA-AuNPs能稳定分散在盐溶液中。Cd2+能优先结合DNA,AuNPs暴露在盐溶液中发生聚集,溶液由红色变成蓝紫色。Pb2+,Cu2+有轻微干扰,其它金属离子无干扰,裸眼可观察的检测下限低至0.5μmol/L。该方法成功用于环境水样中Cd2+检测。A new colorimetric biosensor for the detection of Cd^2 ＋based on Cd^2 ＋-DNA complexes inducing the the aggregation of Au NPs is constructed. Single-stranded DNA（ssDNA） can be absorbed onto Au NP surfaces through Au-N electrostatic attraction. Owing to the mutual repulsion of the negative charge of DNA on each AuNP surface,monodisperse Au NPs existed in the salt solution. Cd^2 ＋can priority in combination with DNA,AuNPs exposed in salt solution,aggregation of the Au NPs occurs and,hence,the color of the solution changes from red to purple blue. Most of metal ions had no obvious interference except for a slight from Pb^2 ＋,Cu^2 ＋. The detection limit of Cd^2 ＋can be as low as 0. 5 μmol / L. The proposed method is successfully applied to determine the concentration of Cd^2 ＋in environmental samples.

关 键 词：CD^2+ SSDNA AuNPs 比色生物传感器 

分 类 号：Q533[生物学—生物化学]