Magnetic transfection with superparamagnetic chitosan-loaded IGFBP nanoparticles and their biosafety.

We prepared the superparamagnetic chitosan nanoparticles (SPCIONPs) to study the application of them as gene vectors using a magnetic transfection system for the targeted treatment of lung metastasis of osteosarcoma. The SPCIONPs were characterized by transmission electron microscopy, Fourier transform infrared spectrometry, superconducting quantum interference device and atomic force microscopy. Their biosafety was determined by cell counting kit-8 (CCK8) and live-dead staining assays. The transfection was detected by laser confocal microscopy. SPCIONPs, which can bind closely to plasmids and protect them from DNA enzyme degradation, were prepared with an average particle size of approximately 22 nm and zeta potential of 11.3 mV. The results of the CCK8 and live-dead staining assays showed that superparamagnetic chitosan nanoparticles loaded with insulin-like growth factor-binding protein 5 (SPCIONPs/pIGFBP) induced no significant cytotoxicity compared to the control group. The result of transfection suggested that pIGFBP emitted a greater amount of red fluorescence in the SPCIONPs/pIGFBP group than that in the chitosan-loaded IGFBP (CS/pIGFBP) group. In conclusion, the prepared SPCIONPs had good biosafety and could be effectively used to transfer pIGFBP into 143B cells, and they thus have good application prospects for the treatment of lung metastasis of osteosarcoma.