in vitro labeling of neural stem cells with poly-l-lysine coated super paramagnetic nanoparticles for green fluorescent protein transfection

background: the magnetic nanoparticle-based transfection method is a relatively new technique for delivery of functional genes to target tissues. we aimed to evaluate the transfection efficiency of rat neural stem cell (nsc) using poly-l-lysine hydrobromide (pll)-coated super paramagnetic iron oxide nanoparticles (spion). methods: the spion was prepared and coated with pll as transfection agent and the transfection efficiency was evaluated in rat nsc using enhanced green fluorescent protein-n1 plasmid containing gfp as a reporter gene. nsc was incubated for 24 h in cell culture media containing 25 µg/ml spion and in different concentrations of pll (0.25, 0.50, 0.75, 1 and 2 µg/ml). cell viability was determined before and after transfection for every concentration using trypan blue assay. characterization of prepared uncoated (spion) and coated (spion-pll) complexes were evaluated by a transmission electron microscope and the zeta potential. results: pll at 0.75μg/ml showed optimal results with 25 μg/ml spion concentration compared with other pll concentrations (0.25, 0.50, 1 and 2 μg/ml). the 18% efficiency with the transfected cells showed green fluorescence. conclusion: transfection with spion is an efficient, non-viral gene transfere method.