Polyamidoamine Dendrimers with a Modified Pentaerythritol Core Having High Efficiency and Low Cytotoxicity as Gene Carriers

Polyamidoamine (PAMAM) dendrimers represent one of the most efficient polymeric gene carriers. This study describes a new family of PAMAM dendrimers that can be synthesized using a Pentaerythritol derivative (PD) as a core that possesses 12 branches. This new approach in the synthesis of divergent dendrimers provided a rapid increase in the number of branches, which made it easier to obtain dendrimers with high generation and large enough molecular size. The PD dendrimers of generations 3-5 synthesized in this study could efficiently condense DNA into nanoscale complexes with slightly positive charges. Their transfection efficiency was evaluated in different cell lines. These PD dendrimers were found to show higher transfection efficiency, but much lower cytotoxicity, than the commercial nonviral gene carriers polyethyleneimine (PEI), polylysine (PLL), and PAMAM dendrimers with an ethylenediamine core (generations 5 and 7). The results indicate that, with high transfection efficiency and low cytotoxicity, the PD dendrimers hold promise as novel nonviral gene carriers.