中文摘要：

Bloomfield很早指出，在DNA凝聚过程中，急剧弯折会导致DNA分子中出现“铰链（kink）”结构，但未见实验证实。基于紫外可见分光光度法，分别在精胺、亚精胺与DNA凝聚体系中加入氟化物以及氯化物，发现二者虽同为卤族，但对精胺一DNA凝聚体系的效应不同。氟离子使精胺-DNA凝聚体系中出现了“蓝移增色”现象，氯离子仅使该体系出现微弱的增色效应，而二者对亚精胺-DNA凝聚体系的效应基本相同，均出现微弱增色效应。基于氟离子特殊性质，设计一种能够有效探测DNA凝聚过程中“铰链（kink）”结构氟化物探针，而且证实，第二类“铰链（kink）”结构出现在精胺-DNA凝聚体系中。

英文摘要：

Bloomfield has pointed out that the kink structure occurs for sharp bending during DNA condensation process, until now, which has not been proved by experiments. Using UV Spectrophotometer, the effects of fluoride and chlorine on the poly- amine-DNA condensation system can be detected. Fluoride and chlorine both belong to the halogen family, but their effects on spermine-DNA condensation system are totally different. Fluoride ions make blue-shift and hyperchromicity appear in the sperm- ine-DNA condensation system, but chlorine ions only make insignificant hyperchromicity happen in this system. Both fluoride i- ons and chlorine ions only make insignificant hyperchromicity happen in spermidine-DNA condensation system. Based on the dis- tinguished character of fluoride, a fluoride-sensor for ＂kink＂ structure in DNA condensation was developed and the second kind of ＂kink＂ structure only appear in the spermine-DNA condensation system.