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Three dimensionally ordered macroporous bioactive SiO 2 CaO Na 2 O P 2 O 5 glass (3DOM BG) is synthesized by using the sol gel method. After an in vitro test in simulated body fluid (SBF), the hydroxyapatite (HAp) crystalline phase is clearly formed on its surface as confirmed by X ray diffractometry (XRD) and Raman spectroscopy. Mag netic 3DOM BG/Fe samples are synthesized by partial substitution of SiO 2 with iron oxide. Whilst the HAp layer is not confirmed, energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and XRD analysis reveal calcium phosphate layer on the surface of 3DOM BG/Fe samples after the SBF soaking. The growth of HAp like layer is slower with increasing iron oxides. The initial mechanism that thought to induce bone forma tion is reduced due to the replacement of Ca 2+ with Fe ions in the glass network. The formation of HAp like layer is modified by the sedimentation of Ca and P while the nonmagnetic 3DOM BG forms the calcium phosphate by the ionic exchange following the Hench mechanism. The adult human adipose tissue derived stem cells (hADSCs) can be closely attached and well spread on the flat plate of all 3DOM BG/Fe and 3DOM BG. Without detectable cytotoxicity possibly induced by iron oxides, the osteoblast can be grown and proliferated. In addition to these bioactivity and biocompatibility, porous structures can allow their possible use in targeted drug delivery and magnetic properties of 3DOM BG/Fe can essentially be implemented in hyperthermia therapy.

In this study, bioactive glass particles with controllable structure and porosity were prepared using dual-templating methods. Block copolymers used as one template component produced mesopores in the calcined samples. Polymer colloidal crystals as the other template component yielded either three-dimensionally ordered macroporous (3DOM) products or shaped bioactive glass nanoparticles. The in vitro bioactivity of these bioactive glasses was studied by soaking the samples in simulated body fluid (SBF) at body temperature (37 ∘ C) for varying lengths of time and monitoring the formation of bone-like apatite on the surface of the bioactive glass. A considerable bioactivity was found that all of bioactive glass samples have the ability to induce the formation of an apatite layer on its surface when in contact with SBF. The development of bone-like apatite is faster for 3DOM bioactive glasses than for nanoparticles.

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Bioactive glass ceramics (BGCs) have been used in orthopedic and dentistry due to having better osteoconductive and osteostimulative properties. This study aimed to evaluate and compare the drug release properties of two different BGCs; 45S5 and S53P4. The BGCs were composed with four phases of SiO2 – CaO – Na2O – P2O5 system, synthesized by sol–gel method using dual templates; a block-copolymer as mesoporous templates and polymer colloidal crystals as macroporous templates, called three-dimensionally ordered macroporous-mesoporous bioactive glass ceramics (3DOM-MBGCs). In vitro bioactivity test performed by soaking the 3DOM-MBGCs in simulated body fluid (SBF) at 37°C. The results indicated that, the 45S5 have the ability to grow hydroxyapatite-like layer on the surfaces faster than S53P4. Gentamicin drug was used to examine in vitro drug release properties in phosphate buffer solution (PBS). The amount of drug release was quantified through UV/Vis spectroscopy by using o-phthaldialdehyde reagent. S53P4 showed high drug loading content. The outcome of drug release in PBS showed that both S53P4 and 45S5 exhibited a slowly continuous gentamicin release. The resultant drug release profiles were fitted to the Peppas-Korsmeyer model to establish the predominant drug release mechanisms, which revealed that the kinetics of drug release from the glasses mostly dominated by Fickian diffusion mechanism.