对荧光探针N-9-吖啶-α-氨基乙酸的合成方法作了改进,使偶氮化反应时间由7 h缩短为3 h,产率由78.9%提高至85.2%.此试剂与铜(Ⅱ)反应使其荧光猝灭,并据此提出了以此试剂为探针的痕量铜的荧光光度测定法.在pH 7.0的缓冲介质中,在一定量的乙醇存在下,铜(Ⅱ)与荧光探针反应,通过测定样品溶液和空白溶液在激发波长(λex) 262.0 nm和发射波长(λem) 456.0 nm的荧光强度FA和FB,计算得反应液荧光强度猝灭程度ΔF,其荧光强度的猝灭程度与铜(Ⅱ)质量浓度在0.20~600.0 μg·L-1范围内呈线性关系,方法的检出限(3σ/b)为0.04 μg·L-1.按此方法分析了3个环境水样,测得其铜量值的相对标准偏差(n=6)均小于2.5%,回收率在96.0%~102.0%之间.

Synthesis of the fluorescence reagent,N-9-acridinyl-α-aminoacetic acid,was improved,resulting a decrease of time for diazotization from 7 h to 3 h,and an increase of yield from 78.9% to 85.2%.Fluorescence quenching effect was observed when the new reagent was reacted with Cu(Ⅱ).The use of the reagent as a fluorescence probe in the determination of trace amounts of copper was proposed.In a buffer solution of pH 7.0,Cu(Ⅱ) was reacted with the fluorescence reagent in the presence of ethanol,the magnitude of derease in fluorescence intensity (ΔF) of the reaction solution was measured at the wavelengths of (λex) 262.0 nm and (λem) 456.0 nm by taking the difference between emission fluorescence intensity of the blank solution FB and the sample solution FA.Linear relationship between values of ΔF and concentration of Cu(Ⅱ) was found in the range of 0.20-600.0 μg·L-1,with its detection limit (3σ/b) of 0.04 μg·L-1.Values of RSD′s (n=6) and recovery found in the analysis of 3 samples of environmental water,were less than 2.5% and in the range of 96.0%-102.0%.