Studies on polyamidoamine dendrimers as efficient gene delivery vector

Non-viral methods of gene delivery are attractive alternatives compared to virus-based gene delivery. Polyamidoamine (PAMAM) dendrimers are a new class of highly branched spherical polymers and have a unique surface of positively charged primary amine groups. They can form complex with DNA by electrostatic interaction, and deliver gene into cells. The ability of G5 PAMAM dendrimers binding and transferring DNA to cells has been investigated, and the effect of this complex to cell viability has been evaluated. G5 PAMAM dendrimers can bind DNA and transfer it to cultured cells efficiently, and have low cytotoxicity. The complex of PAMAM dendrimer-DNA can remain intact in a broad pH range, and also can prevent DNA from being degraded by restriction enzyme. Using the EGFP-C2 gene as marker genes, PAMAM dendrimers can deliver it to many organs after intravenous injection and have high expression in liver, kidney, lung, and spleen. Polyamidoamine- DNA complex can bind selectively plasma proteins, which may be correlated with its transportation in vivo. Polyamidoamine dendrimers' high-efficiency, low-cytotoxicity gene vector, appear to have potential for fundamental research and genetic therapy in vitro and in vivo.