Biocompatibility Analysis and Cancer Therapy Applications of PEG-Iron Oxide Core-Shell Nanoparticles

Composite magnetic nanoparticles provide the opportunity for direct tumor targeting, thermal therapy, and controlled drug release. However, the magnetic nanoparticles must be biocompatible in order to be used in cancer therapy applications. By coating iron oxide magnetic nanoparticles with hydrogels formed from poly (ethylene glycol) 400 dimethylacrylate (PEG400DMA), it is hypothesized that their toxicity can be decreased while maintaining their property of heating in alternating magnetic fields. In this study, it was found that when the concentration of nanoparticles was increased, cell viability of NIH 3T3 fibroblasts and A549 lung cancer cells decreased. For example, the cell viability of NIH 3T3 fibroblasts exposed to 100μg/ml PEG400DMA coated nanoparticles was found to be 66%, while fibroblasts exposed to 500μg/ml PEG400DMA coated nanoparticles had a cell viability of 2%, and exposure to 1000μg/ml resulted in a zero percent viability, after 24 hours of exposure. Cells exposed to iron oxide nanoparticles coated with citric acid had higher viabilities than cells exposed to PEG400DMA coated iron oxide nanoparticles, which was likely a result of differences in particle stability. In the thermal ablation studies, A549 lung cancer cells were exposed to citric acid coated iron oxide nanoparticles at a concentration of 15mg/ml for 3 hours to allow particle interaction. The cells were then exposed to an alternating magnetic field for 10 minutes and incubated for an additional two hours. The heat generated by the magnetic nanoparticles in the alternating magnetic field caused a change in temperature of greater than 15 degrees Celsius, which was enough to induce significant cell death