镓(Ⅲ)与变色酸荧光反应及其应用研究

Fluorescence Reaction of Gallium(Ⅲ) with Chromotropic Acid and Its Application

在PH=4．4的乙酸-乙酸钠缓冲体系中，镓（Ⅲ）与变色酸反应生成新的荧光物质，在λex/λem=242／370nm，测得荧光强度增量△F与镓（Ⅲ）的含量在0～10μg／25mL范围内服从比耳定律。探讨了荧光增强的条件。该方法用于样品分析的线性方程为：△F=26．80c（μg/25mL）＋0．011，相关系数r=0．9991。测定煤样和煤矸石中镓含量分别为6．29mg／kg和10．97mg／kg，加标回收率在96．8％～103．5％之间，相对标准偏差〈5．0％（n=4），与分光光度法相比，结果满意。

A complex compound with an enhanced fluorescence at λex/λem of 242/370 nm can be formed between Ga（ Ⅲ ） and chromotropic acid in HAc-NaAc buffer solution at pH = 4.4, and the fluorescence intensity increase △F is linearly related to the concentration of Ga（ Ⅲ ） in the range of 0-10μg/25mL. The effects of buffer solution, pH, chromotropic acid concentration, reaction temperature and time on the fluorescence intensity were investigated. The regression equation was obtained as iF = 26.80 C（μg/25mL〉 ＋0. 011 with the correlation coefficient （r） of 0. 9991. The method has been used to determine Ga in coal and gangue samples, and Ga concentration of 6.29 mg/kg and 10.97 mg/kg were obtained with the recoveries between 96.8-103.5% and relative standard deviation less than 5% （n=4）, which is comparable to the results obtained from spectrophotometric detection.