Impact of Iron Oxide Phases on the Magnetic Induction Heating Capacity of Mesoporous 45SiO 2 -16.5CaO-24.5Na 2 O-6P 2 O 5 -8Fe 3 O 4 Glass-Ceramics.

Sol-gel-based mesoporous 45SiO 2 -16.5CaO-24.5Na 2 O-6P 2 O 5 -8Fe 3 O 4 bioglass-ceramics were obtained by substituting magnetite nanoparticles for CaO in a 45SiO 2 -24.5CaO-24.5Na 2 O-6P 2 O 5 bioglass composition. To enhance the dissolution of the precursors and to vary the crystalline phases, the as-synthesized ceramic powders were processed for 1 h each at temperatures ( T A ) between 550 and 700 °C. A gradual decline in the saturation magnetization with an increase in T A was observed, which is linked to the gradual conversion of magnetite into hematite at different T A > 550 °C. All of the processed samples indicated a hydroxyapatite surface layer formation in in vitro tests. Aqueous solutions of the ceramic processed at 600 °C exhibited superior magnetic induction capacity. Thus, the substitution of magnetite nanoparticles for CaO in the base composition, coupled with appropriate heat treatment, results in a promising bioactive glass-ceramic for magnetic hyperthermia treatment of deep-rooted cancer cells.