中文摘要：

在生物体中,DNA会凝聚成紧密结构,对于遗传信息的储存和转录有重要意义。对于DNA的凝聚以及伴随的电荷逆转已经有了比较深入的研究,这些研究大多集中于一些水解性较弱的离子,而对于那些易水解对于溶液pH影响较大的金属离子（例如铁离子）的研究较少。本文系统地研究了铁离子引起的DNA电荷逆转和凝聚,通过与DNA在三氯六氨络合钴凝聚的对比,探索了铁离子引起的DNA的电荷逆转和凝聚的可能机制。

英文摘要：

The fact that DNA is condensed into a compact structure in an organism is very important for the storage and transcription of genetic information. Previous intensive studies involve DNA condensation and associated charge inversion. Most of them highlight polyamines and worse hydrolytical ions, but less of them involve easy hydrolytical and pH greatly influenced metallic ion （such as ferric ion）. We systematically investigate ferric ion induced DNA charge inversion and condensation. By comparison with cobalt hexamine,we explore a possible mechanism of ferric ion induced DNA charge inversion and condensation.