Reversible addition–fragmentation chain transfer polymerization with a low-temperature initiator can be used to synthesize multifunctional block copolymers for polyplex formation. Utilizing three methacrylate monomers (triethylene glycol methyl ether methacrylate (MEO₃MA), pyridyldisulfideethyl methacrylate (PDSM), N,N-dimethylethylenediamine methacrylate (DMAEMA)) and an azide bearing chain transfer agent for polymerization, the resulting triblock-copolymers possess two orthogonally reactive functionalities (a block with reactive disulfide side chains and an azide end-group) and two additional functional blocks for i) solubilization and ii) polyplex formation. Thereby, the MEO₃MA block provides solubility in aqueous media and the DMAEMA block, having a tertiary amine in the side chain, allows polyplex formation with polyanionic biomacromolecules like DNA or RNA. Due to the reactive disulfide block the polyplexes can be (reversibly) crosslinked with dithiols. Because of the manifold of possibilities to modify the pDNApolyplexes, this polymers system is an interesting candidate for active-targeting and codelivery approaches.

中文翻译：

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用于复合物形成的反应性多功能三嵌段共聚物的 RAFT 合成

具有低温引发剂的可逆加成-断裂链转移聚合可用于合成多功能嵌段共聚物以形成多聚体。利用三种甲基丙烯酸酯单体（三甘醇甲基醚甲基丙烯酸酯（MEO ₃ MA）、甲基丙烯酸吡啶基二硫醚乙酯（PDSM）、N，N-二甲基乙二胺甲基丙烯酸酯（DMAEMA））和带有叠氮化物的链转移剂进行聚合，得到的三嵌段共聚物具有两个正交反应性官能团（具有反应性二硫化物侧链和叠氮化物端基的嵌段）和两个用于 i) 增溶和 ii) 复合物形成的附加功能性嵌段。因此，MEO ₃MA 嵌段提供在水性介质中的溶解性，而 DMAEMA 嵌段在侧链中具有叔胺，允许与聚阴离子生物大分​​子（如 DNA 或 RNA）形成复合物。由于反应性二硫化物嵌段，复合物可以（可逆地）与二硫醇交联。由于修饰 pDNApolyplexes 的多种可能性，该聚合物系统是主动靶向和共递送方法的有趣候选者。