Synchrotron X-ray Absorption and In Vitro Bioactivity of Magnetic Macro/Mesoporous Bioactive Glasses

Abstract

Iron oxides in macro/mesoporous bioactive glasses were characterized by synchrotron X-ray absorption near edge structure (XANES) spectroscopy. This magnetic phase was introduced by adding Fe(NO 3 ) 3 9H 2 O during the sol-gel synthesis. The obtained bioactive glass scaffolds exhibited superparamagnetism, in which the magnetization was increased with the increase in the Fe molar ratio from 10 to 20%. The linear combination fits of the XANES spectra indicated that the increase in the Fe molar ratio to 20% enhanced the γ-Fe 2 O 3 formation at the expense of the α-Fe 2 O 3 phase. This variation also promoted the formation of fine-grained bone-like apatites on the surface of the scaffolds in the in vitro test. The apatite growth between three and seven days was confirmed by the changing elemental compositions. However, the highest magnetic proportion led to the distortion of the skeleton walls and the collapse of the porous networks.

Enhancement in the induction heating efficacy of sol–gel derived SiO2–CaO–Na2O–P2O5 bioglass-ceramics by incorporating magnetite nanoparticles

“…The magnetic properties of SiO 2 -CaO-Na 2 O-P 2 O 5 -Fe 2 O 3 glasses and glass-ceramics, and SiO 2 coated Fe 3 O 4 core-shell nanoparticles have been investigated towards biomedical applications. [12][13][14]17,18,[41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] A survey of the literature shows that the magnetic properties of the above systems depend strongly on their composition and synthesis route. Rehman et al reported a sol-gel derived mesoporous magnetic glass-ceramic with a composition of 7Fe 3 O 4 -51SiO 2 -18CaO-20Na 2 O-4P 2 O 5 (mol%) containing Fe 3 O 4 with average particle size of 50 AE 10 nm and M s of B13 emu g À1 .…”

Investigation of Bismuth Nano-Bioactive Glass Doped Iron Oxide Formation and Structure Properties on Biocompatibility

“…According to previous study, the band at 545cm -1 was related to and P-O vibration, the band in between 890 and 970 cm -1 is associated with the Si-O which is non-bridging oxygen, while Si-O stretching mode is located in the range 1000-1200 cm -1 , the band at about 1460 cm -1 is due to carbonate group, the band around 1640 cm -1 is related to molecular water, the bands at about 2820, 2928, and 3450 cm -1 are correspond to different modes of water, OH or silanol groups [37,38].…”

Influence of iron oxide substitution on the magnetic interactions in sol–gel‐derived 45S5 bioactive glass–ceramics

“…A few attempts have been made to synthesize FeO and Fe 2 O 3 substituted SiO 2 -CaO-Na 2 O-P 2 O 5 glasses. [17][18][19] Enhanced bioactivity of sol-gel-derived MGC over its bulk counterpart, and the lack of systematic study of magnetic phase evolution and the behavior of iron ions in the glass-ceramic network motivated us to conduct a detailed study on these MGC obtained by substituting iron oxide for silica in the Hench bioglass composition. Structural, magnetic, in vitro bioactivity, and induction heating properties of these MGC developed for bone regeneration and hyperthermia applications are reported elsewhere.…”