Development of Functionalized Iron Oxide Nanoparticles Through Non-Thermal Atmospheric Pressure Plasma Assisted Polymerization for Reducing Cytotoxicity

The study aims to synthesize and homogeneously functionalize iron oxide nanoparticles (IONPs) using a non-thermal atmospheric pressure (NTAP) plasma for biological applications. IONPs were synthesized using a new NTAP plasma assisted electrolysis technique. The utilization of a unique NTAP plasma rotating reactor allows for a uniform surface functionalization throughout the IONP surface. The precursor used for the functionalization process was acrylic acid (AAc), and it was carried out in response to the applied voltage and monomer flow rate. Optical emission spectroscopy (OES) was used to investigate the reactive species in-situ throughout the functionalization process. Vibrating-sample magnetometry (VSM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and X-ray photo electron spectroscopy (XPS) were used to analyse the changes in the chemical, structural, morphological, and magnetic properties of the untreated and functionalized IONPs. Subsequently, chemical dosimetry and the in vitro metabolic activity assay (MTT) were used to analyse the OH• radical production capacity and toxicity of IONPs. The findings showed that the experimental working conditions had a significant impact on retaining the distinctive COOH functional groups on the surface of functionalized IONPs. The coexistence of the hematite (Fe₂O₃) and magnetite (Fe₃O₄) phases is revealed by the untreated and functionalized IONPs, which also exhibit marked super paramagnetic performance and a spherical shape. In the end, the IONPs demonstrated clear nontoxicity when they were functionalized at greater flow rates and reduced applied voltage. The analysis results unequivocally demonstrated the functionalized IONPs’ non-toxicity, highlighting their prospective application in the field of biomedicine.