Papers by Keyword: Bioactive Glass

Abstract: Tantalum-containing phosphate invert glasses were prepared using a liquid phase method under ambient conditions. In our previous study, the ion-releasing behavior (i.e. chemical durability) of phosphate glasses was controlled by the amount of intermediate oxides. In this work, Ta₂O₅ (intermediate oxide) was used to improve the chemical durability of the glasses. Ta-containing phosphate invert glasses were prepared and their structures were characterized. X-ray diffraction (XRD) patterns of the glasses exhibited broad halos, indicating an amorphous state. The amount of P₂O₅ in the glasses increased with increasing Ta₂O₅ content, while the amount of CaO decreased. The glasses prepared with a nominal P : Ta molar ratio of 2 : 1 showed a value of 1.87 : 1. Thus, almost all the Ta used in the synthesis was contained in the resulting glass. Raman spectra showed bands corresponding to short phosphate units such as ortho-and pyrophosphate, and the P-O-P peak was blue-shifted with increasing Ta₂O₅ content. The P-O-Ta bonds were formed with TaO₄ tetrahedra, as new peaks at 970 cm^-1 (P-O-Ta bonds) and 825 cm^-1 (observed in YTaO₄) were observed. The glasses containing higher amounts of Ta₂O₅ exhibited TaO₆-rich phases, as shown by the Raman band at 630 cm^-1 (Ta-O-Ta bonds) and broad XRD peaks at 2θ = 5 ~ 10°. Therefore, Ta in the phosphate invert glasses prepared by the liquid-phase method crosslinks phosphate units in the form of TaO₄ tetrahedra, and the excess Ta exists in the form of TaO₆ octahedra as a network modifier and/or Ta₂O₅-rich phase.

Abstract: Phosphate invert glasses are mainly composed of ortho-and pyro-phosphate units and can stimulate cellular functions by releasing inorganic ions. Our group has succeeded in the synthesis of titanium-containing phosphate invert glasses with the liquid phase method at room temperature. ZnO is classified as an intermediate oxide in the glass network structure and improves the chemical durability of phosphate invert glasses. In addition, zinc ion exhibit a wide range of antibacterial ability. However, excess amounts of zinc ions can be toxic to cells. Hence, the dissolution behavior of zinc ions must be controlled for biomedical applications. In this work, ZnO-containing phosphate invert glasses (PIG-Zn) were prepared using the liquid phase method. The phosphate groups of PIG-Zn were composed of ortho-and pyro-phosphate groups, and the peaks were blue-shifted with increasing the ZnO content due to the field strength of Zn²⁺ being larger than that of Ca²⁺. Thus, phosphate groups may be cross-linked by Zn²⁺ to form P-O-Zn bonds. Meanwhile, ion-releasing amounts from PIG-Zn were decreased with increasing ZnO content. This is because the formation of P-O-Zn bonds can increase the chemical durability of PIG-Zn. In addition, PIG-Zn showed excellent antibacterial ability. Therefore, PIG-Zn is expected to exhibit antibacterial ability with controlled Zn²⁺ ion-releasing behavior for biomedical applications.

Abstract: This study investigates the morphological, structural, and bioactive properties of strontium-doped bioactive glass (Sr-BG) and copper-strontium-doped bioactive glass (Cu-Sr-BG) scaffolds to enhance their potential for biomedical applications. Scanning electron microscopy (SEM) revealed that both Sr-BG and Cu-Sr-BG scaffolds feature smooth, highly porous surface morphologies with interconnected pores (120–150 µm) created using a foaming agent. This pore network facilitates cell attachment and proliferation. Fourier transform infrared (FTIR) analysis confirmed the preservation of the silica network, with characteristic Si–O–Si bending and stretching peaks remaining consistent after Cu doping. X-ray diffraction (XRD) analysis demonstrated that both scaffolds retained an amorphous structure, with Cu doping successfully incorporated without disrupting this feature. Both Sr-BG and Cu-Sr-BG scaffolds exhibited excellent bioactivity, forming an apatite layer on their surfaces after immersion in simulated body fluid (SBF), indicating strong potential for bone tissue engineering applications. These findings suggest that Sr-and Cu-doped bioactive glass scaffolds possess promising characteristics for promoting cell attachment and osteoconductivity, positioning them as viable candidates for future biomedical applications in bone regeneration

Abstract: Bioactive glasses based on the SrBGs: 45SiO2 - 6P2O5 - 15SrO - 34CaO, 5Zn-SrBGs (wt.%): 45SiO2 - 6P2O5 - 15SrO - 29CaO - 5ZnO (wt.%), and 5Ce-SrBGs: 45SiO2 - 6P2O5 - 15SrO - 29CaO – 5CeO (wt.%) were successfully synthesised through the sol-gel process under the acid condition. The concentration of nitric acid at 0.01M was an optimal condition to accelerate the hydrolysis and polycondensation reactions in these systems. SEM images showed the primary particle nucleus growth in the morphological structure of the SrBGs, 5Zn-SrBGs, and 5Ce-SrBGs. FTIR spectra indicated the incorporation of therapeutic cations in the glass structure whilst maintaining the morphological structure. XRD and SEM suggested the crystalline apatite formation on the surface of BGs after the BGs were incubated in the simulated body fluid (SBF) at pH 7.4 for 21 days. EDS-SEM indicated the apatite formation whilst containing doping ions in the glass structure. All three BGs formulations could promote the murine pre-osteoblast cell (MC3T3-E1) cell proliferation at the concentration between 200-250 µg/mL and have no in vitro cytotoxicity on MC3T3-E1 cells up to the concentration of 1mg/mL.

Abstract: There are many requirements for biomaterials used in the applications of bone tissue engineering, besides their biocompatibility, they should exhibit acceptable mechanical properties to mimic bone properties. Many research areas in bioactive materials for bone tissue engineering focused on producing new bioactive glass and ceramic compositions containing a trace of inorganic elements (such as Mg, Sr, Cu, Zn) to combine the mechanical properties and bioactivity. In the present study bioglass-MgO composite material has been used to produce Diopside (CaMgSi₂O₆) by the sintering process. The compact samples were made from a mixture powder of (7, 15)wt% MgO and binary bioglass 70Si-30Ca sintered at 1100 ᵒC for 2 hr. The XRD results confirmed the presence of diopside and wollastonite CaSiO₃ in the case of using 7wt.% MgO while the structure was completely diopside at 15 Wt.% MgO. Physical properties, compressive strength, and hardness were investigated, as well as biodegradation behavior and bioactivity in human saliva were inspected. The results confirmed improving the mechanical properties along with increasing MgO as well as proved the ability to form hydroxyapatite on the surface when exposed to human saliva. These findings demonstrated the positive role of MgO in the mechanical properties of 70Si-30Ca bioactive glass besides producing diopside as a good candidate for hard tissue engineering.

Abstract: In this study, a composite of bioactive glass and cordierite (BG/cordierite) was proposed to increase the strength of bioactive glass (BG). Both BG and cordierite were separately synthesized with the method of glass melting and used to fabricate BG/cordierite with sintering temperature in the range from 600 to 1000 °C. The BG/cordierite were characterized using X-ray diffraction (XRD), density, bulk density, porosity and hardness test. The XRD pattern shows amorphous phase and crystalline phase such as combeite, wollastonite and larnite appeared after sintering. The highest hardness value show by BG/cordierite with sintering temperature 950 °C (BG/C950) with 251 Hv.

Abstract: Polyetheretherketone (PEEK) is a semicrystalline thermoplastic polymer with high chemical resistance, thermal stability and excellent mechanical properties. In the present work, neat PEEK and 3% bioactive glass/PEEK composites were annealed at various temperatures (100 °C, 200 °C and 300 °C) for (30 and 60) min and characterized with mechanical and density tests, differential scanning calorimetery and Fourier transform infrared spectroscopy. Results manifested bioactive glass powder enhanced the properties of the PEEK matrix. Thermal annealing at (200 and 300 ^°C) had a positive influence on the mechanical properties and density owing to increase in the level of crystallinity, whereas annealing at (100 ^°C) had not effect on the properties.

Abstract: The quaternary phase bioactive glasses (SiO₂-CaO-Na₂O-P₂O₅) were synthesized by the sol-gel process. Pluronic P123, using surfactant as structure-directing agents as well as phase separation inducers. The obtained bioactive glasses were characterized regarding morphology by using the scanning electron microscopy (SEM). Polymer colloidal crystals (CCTs) as the template component yielded either three-dimensionally ordered macroporous (3DOM) structure or hollow spheres shaped bioactive glass. The other type of morphology generation is related to the polymerization-induced phase separation (PIPS) in the gelation process. The heterogeneous precursor i.e. silica-rich regions caused the microspheres and solvent-rich areas produced micrometer-scale void space in bicontinuos structure. While the lower pH of starting precursor in 45S4P showed stronger precursor-template interactions than the 53S4P by generating the completely hollow spheres structure.

Abstract: Bioactive glasses (BG) were applied in bone and dental applications as well as in tissue engineering. In this studies, a new bioglass 50S8P (50% SiO₂, 22% CaO, 20% Na₂O and 8% P₂O₅) with different aging time (3, 7, 10 and 15 days) was prepared by sol-gel method. These synthesized glasses were analyzed using X- ray powder diffraction (XRD), Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The bioactivity of all BG is evaluated by incubating the BG powder in Hank's Balanced Salt Solution (HBSS) for 7, 14 and 21 days. Thermal analyses indicated the compositions can be stabilized at 700°C. XRD confirmed the primary crystalline phase was Na₄Ca₄Si₆O₁₈. Formation of silica network is established with the existence of functional group Si-O-Si (tetrahedral), confirmed with FTIR analyses. In vitro test confirm the apatite formation on the BG surface with characteristic of carbonate group (C-O) and P-O band noticed from FTIR and morphology of apatite formation on BG surface was observe using SEM

Abstract: Bioactive glass has high biocompatibility and bioactivity. With specific ion adding, it can show different advantages. Titanium ion can improve the mechanic strength, antibacterial ability of bioactive glass, and stability. In this study, bioactive glass with titanium ion doping by the sol-gel method via various reactive environments was fabricated successfully. The morphology was observed by scanning electron microscopy (SEM). The chemical composition was measured by energy dispersive X-ray spectrometer (EDS). By soaking in SBF, the bioactivity of samples had also been analyzed. The formula of bioglass has been optimized to make the better bioactivity.