RAFT synthesis and DNA binding of biodegradable, hyperbranched poly(2-(dimethylamino)ethyl methacrylate

A study was conducted to demonstrate the reversible addition-fragmentation chain transfer (RAFT) synthesis of a biodegradable hyperbranched cationic polymer, poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA). The RAFT technique was selected to control the polymerization process and obtain low molecular weight branch oligomers with similar chain lengths and low toxicity. A biodegradable disulfide-base dimethacrylate (DSD-MA), 1,2-bis(2-(3-methylbuta-1, 3-dien-2-yloxy)ethyl)disulfane was employed as a cross-link agent to link branched oligomers into hyperbranched structures, with each branch point in the polymer linked by a disulfide bond. Chain transfer agent (CTA), 2-((2-(methacryloyloxy)ethyl)disulfanyl)ethyl 4-cyano-4- (phenylcarbonothioylthio)pentanoate was prepared by the reaction between 2-((2-hydroxyethyl)disulfanyl)ethyl-4-cyano-4-(phenylcarbonothioylthio) pentanoate and methacryloyl chloride in the presence of triethlamine (TEA).