Enhancement of the efficiency of non-viral gene delivery by application of pulsed magnetic fi eld. Nucleic Acids Res

Newapproaches to increase theefficiencyofnon-viral gene delivery are still required. Here we report a simple approach that enhances gene delivery using permanent and pulsating magnetic fields. DNA plasmids and novel DNA fragments (PCR products) containing sequence encoding for green fluorescent protein were coupled to polyethylenimine coated superparamagnetic nanoparticles (SPIONs). The complexes were added to cells that were subse-quently exposed to permanent and pulsating mag-netic fields. Presence of these magnetic fields significantly increased the transfection efficiency 40 times more than in cells not exposed to the mag-netic field. The transfection efficiency was highest when the nanoparticles were sedimented on the per-manent magnet before the application of the pulsating field, both for small (50 nm) and large (200–250 nm) nanoparticles. The highly efficient gene transfer already within 5 min shows that this technique is a powerful tool for future in vivo studies, where rapid gene delivery is required before systemic clearance or filtration of the gene vectors occurs