Synthesis and Characterization of CoFe₂O₄/(SiO₂ - CaO - P₂O₅) Magnetic Bioactive Glass Nanoparticles for Biomedical Applications

Magnetic bioactive glass nanoparticles are emerging as an effective multifunctional system for targeted biomedical applications, including bone regeneration, controlled drug delivery, and magnetic hyperthermia therapy. In this study, magnetic bioactive glass (MBG) nanoparticles with a nominal composition of 60SiO₂-36CaO-4P₂O₅ (mol%) were synthesized by incorporating CoFe₂O₄ nanoparticles as the magnetic phase. The MBG nanoparticles were prepared using the sol–gel method, whereas CoFe₂O₄ nanoparticles were synthesized via the solvothermal method. The magnetic phase was introduced into the glass matrix at concentrations of 2% (MBG2) and 4% (MBG4). Structural characterizations were conducted using X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR), confirming the presence of CoFe₂O₄ in the glass matrix. Morphological analysis was performed using Field Emission Scanning Electron Microscopy (FESEM), which validated the successful adsorption of CoFe₂O₄ nanoparticles into the bioactive glass. UV-Visible spectroscopy revealed a substantial change in the optical absorption behavior of the glass upon the addition of CoFe₂O₄. In particular, the MBG4 sample showed a nearly 50% increase in UV absorption compared to bare glass. Zeta potential measurements indicated that both MBG2 and MBG4 exhibit high colloidal stability, with significantly improved dispersion behavior compared with the pure bioactive glass. Magnetic measurements demonstrated that MBG4 exhibits a markedly higher saturation magnetization than MBG2. From the overall results, the incorporation of CoFe₂O₄ up to 4% was identified as the optimal concentration for the selected glass composition. The combined improvements in optical, colloidal, and magnetic properties highlight the potential of magnetic bioactive glass nanoparticles for biomedical applications, particularly in targeted therapy and magnetic hyperthermia.