Versatile functionalization of amylopectin for effective biomedical applications

Successful gene vectors should be with high transfection efficiency and minimal cytotoxicity. Natural polysaccharides, due to their good biocompatibility and biodegradability, have been widely studied and applied. Amylopectin is one of polysaccharides with dendritic structure and numerous hydroxyl groups that could be used for subsequent modification. In this work, a series of dendritic cationic gene vectors comprising amylopectin backbones and poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) side chains with different lengths (termed as AMY-PDs) were readily prepared by atom transfer radical polymerization (ATRP). The gene condensation ability, cytotoxicity and gene transfection of AMY-PDs carriers were investigated. In comparison with “gold-standard” poly(ethyleneimine) (PEI, 25 kDa), the AMY-PDs exhibited higher transfection efficiency with lower cytotoxicity. AMY-PDs could be further modified with Au nanoparticles (termed as AMY-PD@Au). The potential of the AMY-PD@Au vectors to be utilized as a CT contrast agent for imaging of cancer cells was investigated. Such AMY-PD@Au vectors may realize gene therapy with the ability of real-time imaging.