二甲氧基羟基苯基荧光酮荧光猝灭法测定微量铜

Fluorescence Quenching Method for the Determination of Copper(Ⅱ)with Dimethoxyhydoxyphenylfluone

基于在pH =7.2～ 7.6的三乙醇胺 -盐酸缓冲介质中 ,在表面活性剂CTMAB存在下 ,二甲氧基羟基苯基荧光酮(DMH -PF)与铜反应形成 1:2配合物 ,使体系产生荧光猝灭 ,建立了荧光猝灭法测定铜的新方法。该体系的激发波长λex=5 16nm ,发射波长λem=5 4 6nm ,猝灭量与Cu浓度在 0～0 .0 72mg/L范围内呈线性关系 ,检出限为 0 .0 0 0 4 5mg/L ,体系稳定 ,灵敏度高 ,采用巯基棉分离富集铜 ,用于钢样、茶叶、人发、地下水中微量铜的测定 。

Based on the fact the Cu(Ⅱ),DMH-PF and CTMAB react to form a stable ternary complex and conduce fluorescence quenching in a medium of N(C 2H 4OH) 3-HCl butter (pH=7.2～7.6) and in the presence of CTMAB a new method of fluorescence quenching for the determination of Trace copper(Ⅱ) was proposed.Dimethoxyhydoxyphenylfluone (DMH-PF) has the maximum excitation wavelengths at 516?nm and maximum emission wavelengths at 546?nm. Its constituent is established by the methods of isomolar continuous variation and molar ratio as Cu(Ⅱ):DMH-PF=1:2..The linear range of determination is 0～0.072?mg/L with a detection limit of 0.00045?mg/L.The method is stable and highly sensitive to Coppe(Ⅱ). We use mercaptocotton to separate the concentrated the copper.And the method has been used to detemine trace amounts of Cu(Ⅱ) in hair,tea,water and steel with satisfactory results.