论文部分内容阅读
与其它稀土离子的自身荧光相比，稀土Ｃｅ３＋水合离子的荧光要强得多，并且在很宽的浓度范围内与其浓度成很好的正比关系，因此可以用来确定Ｃｅ３＋离子的浓度．ｔＲＮＡ非常强烈地猝灭Ｃｅ３＋水合离子的荧光．采用荧光滴定的方法研究了Ｃｅ３＋－ｔＲＮＡ体系，并用Ｓｃａｔｃｈａｒｄ方法测量了Ｃｅ３＋离子和ｔＲＮＡ的结合数和结合常数，结果发现：ｔＲＮＡ中有２组Ｃｅ３＋结合位置，其结合常数分别为约１０８ｍｏｌ／Ｌ和１０５ｍｏｌ／Ｌ．向体系中加入精胺可使结合数和结合常数稍微降低．
Compared with the autofluorescence of other rare earth ions, the fluorescence of the rare earth Ce3 + hydrate ions is much stronger and has a good proportional relationship with its concentration over a wide range of concentrations and thus can be used to determine the concentration of Ce3 + ions. The tRNA quenches the fluorescence of Ce3 + hydrated ions very strongly. The Ce3 + -tRNA system was studied by fluorescence titration. The binding number and binding constant of Ce3 + ion and tRNA were measured by Scatchard method. The results showed that there are two groups of Ce3 + binding sites in tRNA with the binding constants of about 108 mol / L and 105mol / L. Adding spermine to the system slightly decreased the number of binding and the binding constant.