Magnetic 3D scaffolds for tissue engineering applications: bioactive glass (45S5) coated with iron-loaded hydroxyapatite nanoparticles.

Magnetic 45S5 bioactive glass (BG) based scaffolds covered with iron-loaded hydroxyapatite (Fe-HA-BG) nanoparticles were obtained and its cytotoxicity investigated. Fe-HA nanoparticles were synthesized by a wet chemical method involving the simultaneous addition of Fe2+/Fe3+ions. BG based scaffolds were prepared by the foam replica procedure and covered with Fe-HA by dip-coating. Fe-HA-BG magnetic saturation values of 0.049 emu g-1and a very low remanent magnetization of 0.01 emu g-1were observed. The mineralization assay in simulated body fluid following Kokubo's protocol indicated that Fe-HA-BG scaffolds exhibited improved hydroxyapatite formation in comparison to uncoated scaffolds at shorter immersion times. The biocompatibility of the materialin vitrowas assessed using human osteoblast-like MG-63 cell cultures and mouse bone marrow-derived stroma cell line ST-2. Overall, the results herein discussed suggest that magnetic Fe-HA coatings seem to enhance the biological performance of 45S5 BG based scaffolds. Thus, this magnetic Fe-HA coated scaffold is an interesting system for bone tissue engineering applications and warrant further investigation.