摘要
在pH为3.0~4.0的范围内,Cu^2+会氧化I-并定量析出单质碘,I2与4,6-二溴荧光素反应,使其荧光发生猝灭.据此可建立一种荧光光谱间接测定微量Cu^2+的方法.初步讨论了I2对二溴荧光素的荧光猝灭机理,认为主要是静态猝灭的作用.该体系的荧光发射波长为λem=531nm.在铜含量12~170μg/mL范围内呈现良好的线性关系,回归方程为△IF=0.3473C+1.5466(C:μg/mL),相关系数r=0.9989,检出限为5.3μg/mL.将该方法用于水样中铜离子的测定,得到较好的结果.
A fluorimetric method has been developed for microdetermination of copper ion in water with 4,6-dibromofluorescein. It's based on the fundamentals that Cu^2+ can oxidize I^- and generate element iodine at pH = 3.0 -4.0, and I2 can reacte with dibromofluorescein and make the fluorescence being quenched. The mechanic of reaction is discussed and wavelength of the solution system's fluorescence-emission is λem=531 nm. The calibration graph is linear over the range 12-170μg/mL with the equation △IF = 0. 347 3 C+1. 546 6(C: μg/mL), r =0. 998 9. and the detection limit is 5.3μg/mL. The method has been applied successfully to the determination of copper ion in the water with a satisfactory results.
出处
《泉州师范学院学报》
2007年第2期71-74,共4页
Journal of Quanzhou Normal University
关键词
4
6-二溴荧光素
荧光猝灭法
碘
铜离子
4,6 - dibromofluorescein
fluorimetric method
iodine
copper ion