基于聚乙烯亚胺修饰的银纳米簇检测钴离子

Determination of cobalt ion based on polyethyleneimine modified silver nanoclusters

以聚乙烯亚胺为稳定剂、AgNO为银源、抗坏血酸为还原剂,采用化学还原法合成了聚乙烯亚胺修饰的银纳米簇,并基于钴离子(Co^(2+))对其的荧光猝灭作用建立了一种检测Co^(2+)的荧光分析方法。机理研究显示由于Co^(2+)与聚乙烯亚胺上氨基的配位作用引起银纳米簇聚集而导致荧光强度降低。在优化的实验条件下,银纳米簇的荧光猝灭程度与Co^(2+)浓度在8.30×10^(-7)-4.17×10^(-4)mol/L范围内呈分段线性,检出限为0.41μmol/L。

Polyethyleneimine(PEI)modifiedsilver nanoclusters(Ag NCs)were synthesized through chemical reduction method by using PEI as stabilizer,AgNOas silve source and ascorbic acid as reducing agent,and it was applied to the detection of cobalt ions.It was found that the fluorescence of the silver nanoclusters was quenched by Co^(2+)for the aggregation of PEI-Ag NCs caused by the coordination between cobalt ion and amino group on polyethyleneimine.Under the optimized experimental conditions,the fluorescence quenching degree of PEI-Ag NCs was piecewise linear with the concentration of cobalt ion in the range of 8.30×10^(-7)-4.17×10^(-4)mol/L,and the detection limit was 0.41μmol/L.