Complexation Induced by Weak Interaction between DNA and PEO-b-P4VP below the CMC of the Polymer

作     者：han miao ya-fen wang hai-yan dong 陈道勇 

作者机构：The State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Fudan University Shanghai 200433 China 

出 版 物：《Chinese Journal of Polymer Science》 (高分子科学（英文版）)

年 卷 期：2017年第35卷第1期

页      面：46-53页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070305[理学-高分子化学与物理] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 

基　　金：financially supported by the National Natural Science Foundation of China(Nos.21334001 and 21574025) 

主　　题：Weak interaction DNA Individual polymer chains Block copolymer Critical micelle concentration 

摘      要：The complexation between circular DNA and individual chains of PEO-b-P4VP with a relatively long PEO block and a short P4VP block is highly controllable when the interaction between DNA and the polymer is weak enough. When one circular DNA chain is taken into consideration, and the polymer concentration is far below its critical micelle concentration （CMC）, polymer chains are absorbed by DNA chain due to the interaction between the negatively charged DNA chain and the slightly positively charged P4VP block chains. After the adsorption/complexation, the DNA chain is converted into a nanoring （type 1）. In the nanoring, the DNA chain is sufficiently wrapped by the polymer and adopts a fully stretched conformation, so that the DNA compact ratio in the nanorings is close to 1. When the polymer concentration is close to but lower than the CMC, the free polymer chains in the solution are adsorbed not only by the DNA chain but also by the polymer chains that have already been adsorbed on the DNA chain. As a result, the circular DNA chain adsorbs more polymer chains, and thus the resultant nanoring （type 2） has a larger width. In the type 2 nanoring, the DNA chain is slightly compressed; the DNA compact ratio is only about 2-3. Therefore, complexation induced by the weak interaction between DNA and PEO-b-P4VP below the CMC can produce narrow-disperse and large nanorings with a perimeter of micrometers, which are difficult to prepare by existing methods.