Cytotoxicity and Cell Cycle Effects of Bare and Poly(vinyl alcohol)-Coated Iron Oxide Nanoparticles in Mouse Fibroblasts

Super‐paramagnetic iron oxide nanoparticles (SPIONs) are recognized as powerful biocompatible materials for use in various biomedical applications, such as drug delivery, magnetic‐resonance imaging, cell/protein separation, hyperthermia and transfection. This study investigates the impact of high concentrations of SPIONs on cytotoxicity and cell‐cycle effects. The interactions of surface‐saturated (via interactions with cell medium) bare SPIONs and those coated with poly(vinyl alcohol) (PVA) with adhesive mouse fibroblast cells (L929) are investigated using an MTT assay. The two SPION formulations are synthesized using a co‐precipitation method. The bare and coated magnetic nanoparticles with passivated surfaces both result in changes in cell morphology, possibly due to clustering through their magnetostatic effect. At concentrations ranging up to 80 × 10−3 M, cells exposed to the PVA‐coated nanoparticles demonstrate high cell viability without necrosis and apoptosis. In contrast, significant apoptosis is observed in cells exposed to bare SPIONs at a concentration of 80 × 10−3 M. Nanoparticle exposure (20–80 × 10−3 M) leads to variations in both apoptosis and cell cycle, possibly due to irreversible DNA damage and repair of oxidative DNA lesions, respectively. Additionally, the formation of vacuoles within the cells and granular cells indicates autophagy cell death rather than either apoptosis or necrosis. The impact of high concentrations of super‐paramagnetic iron oxide nanoparticles (SPIONs) on cytotoxicity and cell‐cell effects is studied through the interaction between mouse fibroblast cells with uncoated SPIONs and SPIONs coated with PVA. Significant apoptosis is observed for the uncoated nanoparticles, while the coated nanoparticles demonstrate high cell viability without necrosis and apoptosis even at high concentrations. Since no significant traces of cell death are observed with the coated nanoparticles at low concentrations, the DNA repair pathway appears to have been activated. The formation of vesicles and increased granularity within the cells leads to autophagy cell death for both types of SPION.