摘要
Ｃｅ３＋水合离子可以发出很强的荧光，而这种荧光在Ｃｅ３＋离子与含羧酸根或磷酸根基团的配体形成配合物时完全淬灭，Ｃｅ３＋离子的这一性质可用来确定Ｃｅ３＋配位体系的结合常数。首先由于Ｃｅ３＋水合离子的荧光强度与其自身的浓度成正比，因此可以从荧光强度的大小来推出它的浓度，然后根据Ｓｃａｔｃａｈｒｄ方法计算出体系的结合常数。以丙二酸和ＡＭＰ（单磷酸腺苷）两种配体为例检验了这种方法，所得结果与前人的结果很接近。与其它常用的镧系离子发光方法相比，Ｃｅ３＋发光方法不需要特殊仪器，同时可用于研究许多用Ｅｕ３＋或Ｔｂ３＋发光方法不能研究的有机或生物分子，因而是一种有前途的新方法。
Fluorescence of Ce 3+ (aq) is very strong, but it is thoroughly quenched when Ce 3+ forms complexes with ligands containing carboxylate or phosphate groups. This property is employed to develop a new simple method to determine formation constants of Ce 3+ complex system. Fluorescence intensity is used to determine concentration of Ce 3+ (aq) in complex solution, for it is directly proportional to the concentration of Ce 3+ (aq). In this paper, two examples, Ce 3+ malonic acid and Ce 3+ AMP(adenosine 5′ monophosphate) of fluorescence titration were made and association constants and association numbers of the two systems were deduced for the titration with Scatchard plot. The results are similar to those obtained by others. It is suggested that this Ce 3+ method is a promising fluorescence probe, as it is not only simpler but also superior to other lanthanide fluorescence probe in being able to study a large amount of organic ligands and biomolecules.
出处
《中国稀土学报》
CAS
CSCD
北大核心
1998年第3期203-207,共5页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金
国家科委攀登计划资助项目
关键词
荧光探针
结合常数
测定
铈离子
配位体系
Rare earths, Cerium, Fluorescence probe, Formation constant determination
