Development and Evaluation of Magnetic Bone Cements Based on HAp-Fe3O4 and HAp-CoFe2O4 for Biomedical Applications

This study developed a bone cement based on hydroxyapatite (HAp) and magnetically activated with cobalt ferrite (CoFe2O4) and magnetite (Fe3O4) nanoparticles for potential use in orthopedic surgeries like vertebroplasty. Magnetic nanoparticles (MNPs@SiO2) were mixed with HAp in varying ratios (30:70, 50:50, 70:30) and incorporated into a hydrogel matrix of carboxymethylcellulose, glycerin, and distilled water, forming fluid-viscous magnetic cements. These were analyzed through XRD, SEM, swelling degree, pH, setting time, mechanical strength, magnetic properties, and cell viability. XRD confirmed the crystalline phases of each component, while SEM revealed hybrid morphologies with micropores. Cements with higher HAp content exhibited greater swelling in simulated body fluid (SBF) and faster reaction kinetics, with swelling values between 58% and 91%. After 7 days in SBF, the pH stabilized between 7.0 and 7.3, ensuring biocompatibility. Setting times ranged from 12 to 25 minutes, making them suitable for clinical use. Compressive strengths of 28.91 MPa and 30.06 MPa were achieved after 14 days, indicating structural stability. Ferrimagnetic behavior was observed, with magnetizations reaching 27.30 emu/g for magnetite and 31.08 emu/g for cobalt ferrite. All formulations exhibited non-cytotoxic behavior, confirming their safety for biomedical applications.