The effect of fluorination on the transfection efficacy of surface-engineered dendrimers

Dendrimers have shown great promise in the design of high efficient and low cytotoxic gene vectors. In this study, we synthesized a list of fluorobenzoic acid-modified dendrimers by a facile synthetic route and explored their potential applications as non-viral gene vectors. Fluorination on the aromatic rings significantly improves the transfection efficacy of benzoic acid-modified dendrimers. The transfection efficacy increases with increasing number of fluorine atoms on the aromatic rings of the conjugated benzoic acid. The most efficient conjugate shows superior efficacy to polymer-based commercial reagents such as SuperFect and PolyFect, and comparable efficacy to lipid-based commercial reagents such as Lipofectamine 2000. In addition, the fluorobenzoic acid-modified dendrimers show low cytotoxicity on the transfected cells. The improved transfection efficacy of fluorobenzoic acid-modified dendrimers is due to enhanced cellular uptake and/or easier DNA unpacking behavior compared to non-modified dendrimers. These results provide a new fluorination strategy to generate a library of highly efficient and non-cytotoxic polymeric gene vectors.