Purpose: To study the application of superparamagnetic chitosan nanoparticles (SPCIONPs) as gene vectors using a magnetic transfection system for the targeted treatment of lung metastasis of osteosarcoma.

Methods: The superparamagnetic chitosan nanoparticles were characterized by Transmission Electron Microscopy, Fourier Transform Infrared spectrometry, a Superconducting Quantum Interference Device and Atomic Force Microscopy. Their biosafety was determined by cell counting kit-8 (CCK8) and live-dead staining assays. In vitro transfection was detected by laser confocal microscopy.

Results: SPCIONPs, which can bind closely to plasmids and protect them from DNA enzyme degradation, were prepared with an average particle size of 95.60 nm and zeta potential of 11 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/pIGFBP5) induced no significant cytotoxicity compared to the control group. The in vitro transfection result suggested that pIGFBP5 emitted a greater amount of red fluorescence in the SPCIONPs/pIGFBP5 group than that in the chitosan-loaded IGFBP5 (CS/pIGFBP5) group.

Conclusion: The prepared SPCIONPs had good biosafety and could be effectively used to transfer pIGFBP5 into 143B cells, and they thus have good application prospects for the treatment of lung metastasis of osteosarcoma.

We used CCK8 to detect cytotoxicity, with 5 accessory holes in each group. After removing the maximum and minimum values, 3 values were left for statistical analysis to eliminate errors.