Synthesis of Multifunctional PAMAM-Aminoglycoside Conjugates with Enhanced Transfection Efficiency

The development of multifunctional vectors for an efficient and safe gene delivery is one of the major challenges for scientists working on the gene therapy field. In this context, we have designed a novel type of aminoglycoside-rich dendrimers with a defined structure based on polyamidoamine (PAMAM) in order to develop efficient, non-toxic gene delivery vehicles. Three different conjugates, i.e. PAMAM G4-neamine, -paromomycin, and -neomycin, were synthesized and characterized by nuclear magnetic resonance (NMR) and MALDI analysis. The conjugates were found to self-assemble electrostatically with plasmid DNA and, unlike neamine conjugate, each at its optimum showed increased gene delivery potency compared to PAMAM G4 dendrimer in three different cell lines, along with negligible cytotoxicity. These results all disclosed aminoglycosides as suitable functionalities for tailoring safe and efficient multifunctional gene delivery vectors.