The effect of magnesium content on in vitro bioactivity,biological behavior and antibacterial activity of sol–gel derived 58S bioactive glass

Bioactive glasses (BGs) have a great potential for bone replacement and regeneration in bone tissue engineering applications. In this research, first, sol–gel derived magnesium substituted 58?S BGs (MBGs) series composed of 60SiO₂–4P₂O₅-(36-x) CaO- xMgO, (x = 0; 1; 3; 5; 8 and 10?mol.%) were synthesized and stabilized at 700?°C to eliminate the nitrates and prevent the crystallization of MBGs. MgO was substituted for CaO in the BG formula up to 10?mol% and the effect of Mg concentration on in vitro bioactivity and cellular properties of the MBGs were investigated by immersing them in simulated body fluid (SBF) followed by structural characterization using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The effects Mg on proliferation and differentiation of osteoblastic MC3T3-E1 cells were also evaluated by 3-(4,5dimethylthiazol-2-yl)??2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphate (ALP) activity.Results revealed that magnesium-substituted 58?S BG with 5?mol% MgO (BG-5) had the highest formation rate of hydroxyapatite (HA) while substitution of 8?mol% and10 mol% MgO (BG-8 and BG-10) lowered the bioactivity. MTT and ALP results confirmed that the substitution of the MgO up to 5?mol% increased both proliferation and differentiation of MC3T3-E1 cells, while more substitution had a negative effect and resulted in a decrease of proliferation and differentiation in BG-8 and BG-10. The result of antibacterial test showed that MBGs exhibited antibacterial effect against methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Taken together, results suggest that, among all the synthesized MBGs, sample BG-5 is a promising candidate as multifunctional biomaterial for bone tissue engineering with maximum cell proliferation and ALP activity, good bioactivity and high antibacterial efficiency against MRSA bacteria. Eventually, the BG-5 is suggested to be used in segmental defects in rat model in vivo.     

Characterization,in vitro bioactivity and biological studies of sol-gel synthesized SrO substituted 58S bioactive glass

Bioactive glasses (BGs) are considered as a high potential candidate in bone repair and replacement. In the present study, sol–gel derived BGs based on 60% SiO₂-(36%-x) CaO-4%P₂O₅-x SrO (where x = 0, 5 and 10 mol%) quaternary system were synthesized and characterized. The effect of Sr substitutions on bioactivity, proliferation, alkaline phosphatase activity of osteoblast cell line MC3T3-E1 and antibacterial activity were investigated. Dried gels were stabilized at 700 °C to eliminate the nitrates and prevent the crystallization of bioactive glasses. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy results confirmed the formation of hydroxycarbonate apatite on the BG surfaces. The 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and alkaline phosphate activity results showed that 5% SrO increased both differentiation and proliferation of MC3T3-E1 cells, while 10% SrO resulted in a decrease in bioactivity. Live/Dead and DAPI/Actin staining exhibited viable cell and the morphology of actin fibers and nuclei of MC3T3 cells treated with BG-0 and BG-5. The result of antibacterial test showed that strontium substituted 58S BG exhibited antibacterial effect against methicillin-resistant Staphylococcus aureus bacteria. Taken together, results suggest that 58S BG with 5 mol% SrO is a good candidate for bone tissue engineering with maximum cell proliferation and ALP activity, good bioactivity and high antibacterial efficiency.     

Preparation,characterization and in vitro biological response of simultaneous co-substitution of Zr+4/Sr+2 58S bioactive glass powder

In the present study, structure of zirconium-containing bioactive glass (58S-BG (Zr-BG)) with optimal fixed Zr content (5 mol.%) was modified by incorporation of strontium (Sr). These Zr and Sr-containing BGs (ZS-BGs) were synthesized by sol-gel method and substitution of Ca with modifier ions (Sr content = 0, 3, 6, 9, and 12 mol.%). The results obtained from characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and energy-dispersive X-ray spectroscopy (EDS) techniques from surface of all the ZS-BGs revealed formation of hydroxyapatite (HA) after 7 days of immersion in the simulated body fluid (SBF) solution. Evaluation of changes in the SBF solution, by monitoring pH variations and ions? concentration, was in agreement with the results of morphological and structural investigations. The in-vitro biological function of synthesized BGs was studied through (MTT) assay and alkaline phosphatase (ALP) activity analysis. The results showed that all the specimens significantly stimulated proliferation and viability of MC3T3 osteoblast-like cells. Furthermore, antibacterial studies confirmed less resistance of methicillin-resistant Staphylococcus aureus (MRSA) bacteria against ZS-BGs. Eventually, the results of in-vitro bio-analysis were clarified and confirmed by two cell staining techniques of Live/Dead and Dapi/Actin. This confirmation was achieved by observing the increased quantity of live cells and their nuclei as well as the decreased number of dead cells after co-culturing with all ZS-BGs.     

Bioactive Glass: An In-Vitro Comparative Study of Doping with Nanoscale Copper and Silver Particles

Bioactive glasses (BGs) based on 50SiO₂-45CaO-5P₂O₅ system doped with 1, 5, and 10 mol% CuO or Ag₂O were separately synthesized using quick alkali sol-gel method. Scanning electron microscope (SEM) analysis of the samples confirmed the formation of nano-sized BGs, whereas Fourier transform infrared (FTIR) spectra showed characteristic peaks for silica and phosphate groups. X-ray diffraction (XRD) pattern of the heat-treated (700°C) samples revealed the presence of crystalline metallic silver phase in all Ag-doped samples, while the XRD pattern of Cu-doped and control sample (50Si-45CaO-5P₂O₅) also heat-treated at 700°C confirmed their amorphous nature. Ultraviolet–visible (UV-Vis) studies along with Energy-dispersive X-ray spectroscopy (EDX) analysis confirmed the successful incorporation of Cu and Ag in bioglass. Antibacterial properties of the synthesized BGs were investigated by quantitative viable count method, and the results were related to the ion release profiles of the samples studied by flame atomic absorption spectroscopy (FAAS). Fast initial release of Ag observed in this study makes Ag-doped BG a better rapid bacteria-killing agent than Cu-doped BG, which exhibited a prolonged release of ions, suggesting that it may be a better candidate for long-term antibacterial protection.     

Formation of apatite nano-needles on novel gel derived SiO2-P2O5-CaO-SrO-Ag2O bioactive glasses

A novel SiO₂-P₂O₅-CaO-SrO-Ag₂O bioactive glass containing from 0 to 10 mol% Ag₂O was produced via the sol-gel method. The influence of silver content on in vitro hydroxyapatite (HA) formation, antibacterial and cell viability properties were investigated. The apatite shape and structure were evaluated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD). The results demonstrated that the rate of formation of crystalline HA on SiO₂-P₂O₅-CaO-SrO-Ag₂O bioactive glass containing 5% Ag₂O (BG-5A) was higher in comparison with other specimens. Formation of apatite nano-needles on the SiO₂-P₂O₅-CaO-SrO-5%Ag₂O surface in vitro, after 3 days soaking in SBF solution, demonstrated high bioactivity. The alkaline phosphatase (ALP) and 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay evaluation methods illustrated that the presence of low silver (3% and 5% Ag₂O) had stimulating effect on promoting both differentiation and proliferation of G292 osteoblastic cells. Finally, results offer that specimen BG-5A is well candidate for bone tissue application with considerable high antibacterial potential, bioactivity and optimal cell viability.     

Effect of TiO2 on microphase development during phase separation and crystallization in Na2O–B2O3–SiO2 glass system

This study examines the incorporation of TiO₂ into sodium borosilicate glasses and its effect on the formation of glassy and crystalline microphases. Glasses in the composition range: 7Na₂O–23B₂O₃–(70 - X)SiO₂–XTiO₂ (where X = 0–14.6 mol.% TiO₂) which exhibit phase separation were investigated. Raman studies confirm the formation of two different TiO₂ coordinations depending on the molar content of TiO₂. Thermal properties of glasses are unaffected by TiO₂ addition. The domain size of microphase development in TiO₂-containing glass indicates competition between phase separation and crystallization. Enrichment of titanium on the interphase between glassy microphases reduces the mass transfer and consequently limits the growth rate of glassy phases. This competes with the formation of anatase for which a nucleation-controlled mechanism is proposed.     

In vivo toxicological evaluation of barium-doped bioactive glass in rats

Bioactive glasses (BGs) are inorganic biomaterials with several FDA-approved marketed products, mainly for orthopedic and dental applications. However, in the last few decades, the soft tissue regenerative potential of BGs has also been established preclinically, and its clinical translation requires elaborate in vivo toxicity studies for future biomedical applications. Thus, in the present study, we evaluated the comparative acute and sub-acute toxicity of orally administered barium-doped BG (BaBG) with 45S5 in rats. The lethal dose (LD₅₀) of BaBG and 45S5 was more than 2000 mg/kg body weight (b.w.), with no mortality at the highest dose tested. The oral acute toxicity study was performed at doses of 300 and 2000 mg/kg b.w. according to OECD 423. The organ coefficients of vital organs and histological analysis affirmed the safety profile of BaBG. Moreover, various biochemical indices like alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatinine, and CK-MB confirmed that BaBG did not cause organ toxicity at all doses tested. Similarly, the repeated dose 28-days sub-acute toxicity study was performed according to OECD 407 at doses 50, 500, and 1000 mg/kg b.w. There was no alteration in the hematological parameters, which ascertains that BaBG had no toxic effects on the hematopoietic centers like 45S5. Furthermore, there was no observed neuro-behavioral toxicity of 45S5 and BaBG. Thus, these findings confirm that BaBG is non-toxic and can be used for therapeutic applications in different disease models.     

Alternating Current Electrophoretic Deposition of Antibacterial Bioactive Glass-Chitosan Composite Coatings

Alternating current (AC) electrophoretic deposition (EPD) was used to produce multifunctional composite coatings combining bioactive glass (BG) particles and chitosan. BG particles of two different sizes were used, i.e., 2 μm and 20–80 nm in average diameter. The parameter optimization and characterization of the coatings was conducted by visual inspection and by adhesion strength tests. The optimized coatings were investigated in terms of their hydroxyapatite (HA) forming ability in simulated body fluid (SBF) for up to 21 days. Fourier transform infrared (FTIR) spectroscopy results showed the successful HA formation on the coatings after 21 days. The first investigations were conducted on planar stainless steel sheets. In addition, scaffolds made from a TiAl4V6 alloy were considered to show the feasibility of coating of three dimensional structures by EPD. Because both BG and chitosan are antibacterial materials, the antibacterial properties of the as-produced coatings were investigated using E. coli bacteria cells. It was shown that the BG particle size has a strong influence on the antibacterial properties of the coatings.     

The Effect of Coating TiO<Subscript>2</Subscript> on the CO Oxidation of the Pt/γ-Alumina Catalysts

Abstract  

The effect of coating TiO₂ on the CO oxidation of the Pt/γ-alumina catalysts was observed through activity tests and surface characterization spectroscopy by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) experiments. XPS results evidenced the occurrence of different Pt²⁺ species and metallic Pt⁰ at the surface which suggest electron transfer of titanium (cation) to the platinum atom and the reduction of titanium (Ti⁴⁺ → Ti³⁺). FTIR analyses suggested oxygen spillover mechanism at the interface between titanium dioxide and platinum that may explain the catalytic activity of the platinum titania-supported catalysts. The apparent activation energy for the CO oxidation was 52.5 kJ/mol and similar for all catalysts. However, the frequency factor changed significantly, indicating interfacial phenomena caused by CO and oxygen adsorptions over TiO _x species and Al₂O₃ support with similar dispersions.     

Spark Plasma Sintered HA‐Fe3O4‐Based Multifunctional Magnetic Biocomposites

Although HA is highly biocompatible, one of the major disadvantages of HA include the lack of antibacterial property. In an earlier study, we demonstrated the potential role of magnetic field stimulation on bactericidal property in vitro. Following this, it was hypothesized that antibacterial property can be realized if bacteria are grown on magnetic biocomposites in vitro. In addressing this issue, this study demonstrates the development of HA‐Fe₃O₄‐based magnetic substrate with multifunctional properties. For this purpose, HA‐xFe₃O₄ (x: 10, 20 and 40 wt%) powder compositions were sintered using uniquely designed spark plasma sintering conditions (three stage sintering with final holding temperature of 1050°C for 5 min). A saturation magnetization of 24 emu/g is measured with HA‐40%Fe₃O₄. Importantly, all the HA‐Fe₃O₄ composites demonstrated bactericidal property by rupturing the membrane of Escherichia coli bacteria, while supporting cell growth of metabolically active human fetal osteoblast cells over 8 d culture. A systematic decrease in bacterial viability with Fe₃O₄ addition is consistent with a commensurate increase in reactive oxygen species (ROS).     

Fabrication and in vitro studies on bioactive borate glasses containing dopant chromium sulfate

This research aims to assess the bioactive properties of the modified borate glasses containing extremely low concentrations (≤5 mol.%) from chromium sulfate (Cr₂(SO₄)₃). The glasses in the system xCr₂(SO₄)₃.(60–x)B₂O₃.15CaO.15Na₂O.10P₂O₅, where x = 0, 1, 2, and 5 mol.% were prepared by the melt quenching technique. All glass samples have been treated thermally at 600 °C for 6 h. Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) measurements were carried out to differentiate between the structural changes before and after soaking in the simulated body fluid (SBF) at about 37 °C for 1, 2, and 3 weeks. Glass-ceramic samples have showed sharper peaks that are identified using X-ray diffraction data. These crystalline phases are indexed to crystalline calcium borate (Ca₂B₂O₃) and calcium phosphate (Ca₃(PO₄)₂). In vitro tests, FTIR spectra revealed two small bands in the 560-610 cm⁻¹ range which might be assigned to the formation of a hydroxyapatite layer (HA). The formation of HA was also confirmed by XRD results, particularly after immersion in SBF for 21 days. The study suggests that the presently studied glasses containing Cr₂(SO₄)₃ can possess good bioactivity which might be considered to be suitable for some bio and medical applications.     

Electrodeposition of graphene oxide-hydroxyapatite composite coating on titanium substrate

In this work, graphene oxide (GO)/hydroxyapatite (HA) composite coatings were successfully prepared on titanium substrate by electrophoretic deposition technology. Subsequently, microstructure, phase composition, adhesion strength, hydrophilicity, corrosion resistance, bioactivity, antibacterial activity and biocompatibility of the coating were evaluated. The adhesion strength of coating increased by 76% from 6.46 MPa to 17.81 MPa with 0 wt% GO to 12 wt% GO and the corrosion rate of coating with 8 wt% GO was achieved at the minima of (1.493 × 10^-3mm/a). Biomineralization experiment indicated the excellent bioactivity of GO/HA composite coatings. The water contact angle of the composite coatings increased from 20.6°(0 wt% GO) to 38.1°(12 wt%GO). The antibacterial rates of coating with 5 wt% GO was 96.7%, while declined to 25% after thermal treatment. In-vitro L929 cell culture experiments indicated the composite coatings with 5 wt% GO exhibited good biocompatibility.     

Ex situ and in situ characterization studies of spin-coated TiO2 film electrodes for the electrochemical ozone production process

An electrode composed of silicon/titanium oxide/platinum/titanium dioxide (Si/TiO_X/Pt/TiO₂) was fabricated by spin-coating TiO₂ multilayers on a Si/TiO_X/Pt substrate and was used in electrochemical ozone production (EOP). EOP was realized when the Si/TiO_X/Pt substrate was completely covered with the TiO₂ film and a current efficiency of 7% was achieved at a low current density of 26.7 mA cm⁻² in 0.01 M HClO₄ at 15 °C. The TiO₂ film was found to be of an anatase-type TiO₂ and that to comprise aperture structures from the X-ray diffraction (XRD) and transmission electron microscopy (TEM) observations. Moreover, the fabricated TiO₂ film was found to be an n-type semiconductor by photoelectrochemical measurements. The high efficiency at a low current density of EOP on the TiO₂ n-type semiconductor was explained to result from the electron transfer through the TiO₂/HClO₄ interface as tunneling current. When the tunneling current passes through a depletion layer of TiO₂, the electrode potential is necessarily high enough to facilitate EOP.     

Cellulose-reinforced bioglass composite as flexible bioactive bandage to enhance bone healing

Low mechanical strength of cellulose nanofiber (CNF) and its lack of osseoconductivity in physiological media limit its application for bone tissue regeneration. To resolve these limitations, the densely packed cellulosic layers with thickness of ~50 μm impregnated by 58S bioglass (BG) nanoparticles was made-up (via the simple method of vacuum filtration) in this study. The developed fabrics showed uniform distribution of BG nanoparticles and effectively wrapped between CNF layers which caused sustained ion release into the SBF × 5 solution. The FTIR spectrum of the fabric after the SBF test was illustrated the presence of newly formed HA on the fabric. Also, no significant difference in the hydrophilicity of pure CNF and the developed fabric was presented by AFM results. Alkaline phosphatase activity (ALP) and cytotoxicity evaluation were performed to investigate cell treatment of the fabric which indicated its superior osteogenic potential of developed fabric compared with pure CNF. The increase in osseoconductivity of the developed fabric caused better cell attachment thanks to the interconnected CNFs network. Effective integration of BG nanoparticles between CNF interlayers increased Young's modulus of the developed fabric by 50% that mitigated swelling and enhanced structural stability of CNFs in the SBF × 5 solution. Thus, developed fabric could be considered as an appropriate biomaterial such as a bandage around cracked bone before metallic implantation with good mechanical integrity of the layered constructs obtained as well as strength and swelling.     

Micromechanical properties of hydroxyapatite nanocomposites reinforced with CNTs and ZrO2

This study examined the mechanical properties, wettability, and tribology of hydroxyapatite (HA)–zirconia (ZrO₂)–carbon nanotube (CNTs) ceramic nanocomposites (with various CNT ratios (x): 1, 5, and 10 wt%). HA–ZrO₂–CNT-x powders were hydrothermally synthesized. Hot isostatic pressing (HIP) and cold isostatic pressing were used to manufacture solid and dense tablets; consolidation was performed by sintering the nanocomposites under Ar gas at 1150 °C during HIP. The microstructure and morphology of the nanocomposites were characterized via transmission electron microscopy, energy-dispersive X-ray spectroscopy, powder X-ray diffractometry, Fourier transform infrared (FTIR), and scanning electron microscopy. The effects of ZrO₂ and CNTs on the mechanical characteristics of the nanocomposites were examined via nanoindentation, reciprocating wear, and Vickers hardness tests. The microhardness of HA–ZrO₂–CNT-1% and HA–ZrO₂–CNT-5% increased by 36.8% and 66.67%, respectively, compared with that of pure HA. The nanohardness of the HA–ZrO₂–CNT-1%, HA–ZrO₂–CNT-5%, and HA–ZrO₂–CNT-10% samples was 8.3, 9.65, and 8.02 Gpa, and the corresponding elastic modulus was 83.72, 114.34, and 89.27 GPa, respectively. Both of these parameters were higher than those of pure HA. However, in the nanocomposite reinforced with 10% CNT, as opposed to those with lower CNT ratios, their values were lower. Additionally, HA–ZrO₂–CNT-10% was the most hydrophilic nanocomposite synthesized in this study with a contact angle of 48.8°.     

In vitro evaluation and mechanical studies of MgO added borophosphate glasses for biomedical applications

The objective of current research is to evaluate the bioactive and tribological properties of the MgO doped borophosphate glass system. The glass system constituted of 40% B₂O₃ - (20-x) % CaO – 25% Li₂O – 15% P₂O₅ – x % MgO (mol%), x = 0, 0.5, 01, 02, 03 and synthesized using the melt quench technique. In-vitro bioactivity was determined using simulated body fluid (SBF) at 37 °C with time intervals of 7, 14 and 21 days. Hydroxyapatite (HA) layer formation was assessed using characterization techniques like XRD, FTIR and FESEM-EDS for structural, functional and morphological analysis respectively. The effect of MgO content on microhardness and tribological properties was studied by making cylindrical shaped glass samples. MTT assay was performed for various doses (62.5–1000 μg/ml) of glass dilutions using MG-63 cell line. In-vitro bioactivity showed higher Ca/P ratio with increase in MgO content after 21 days of immersion. MgO content seemed to promote degradation of glass due to formation of open structure in glass network. Borophosphate glass having 3% MgO exhibited the highest hardness value of 5.79(±0.08) GPa with minimum specific wear rate of 1.86 × 10^?11 and 1.38 × 10^?11 m³/Nm at a load of 15 N and 20 N respectively. MTT assay demonstrated the non-toxic behaviour of glass samples even at a higher dose level of 1000 μg/ml which confirmed its biocompatible behaviour. The study suggests that produced MgO doped borophosphate glass exhibits essential characteristics of bioactive materials and hence could be effective in bone filling and wound healing applications.     

Hydrothermally crystallized Sr-containing bioactive glass film and its cytocompatibility

Sr-containing bioactive glass film with the Sr/(Ca+Sr) atomic ratio of 20% was sol-gel coated on titanium substrate, followed by hydrothermal treatment in a mixed phosphate solution (8 mM CaHPO₄ and 2 mM SrHPO₄) and other media at 120 or 140 °C. X-ray diffraction (XRD) analysis confirms amorphous nature of the gel powder calcined at 610 °C, but small peaks of Ca_1.8Sr_0.2SiO₄ or Ca_1.5Sr_0.5SiO₄ are also present. The absorption bands of Si-O-Si, PO₄ and OH groups and a weak absorption band of NO₃ groups appear in FT-IR spectrum of the calcined gel powder. Hydroxyapatite (HA) is detected for the hydrothermally treated sample by XRD and Raman analyses. Sr-containing HA nanocrystallites are formed on the film through a dissolution and precipitation mechanism in the hydrothermal treatment. The appearant bonding strength is 21±1 MPa for the both samples. In the test with MC3T3-E1 cells, the two coated samples exhibit larger viability, higher ALP levels and better cell morphology than the polished sample.     

Apatite formation on melt-derived bioactive glass powder based on SiO2-CaO-Na2O-P2O5 system

The higher melting temperature and longer soaking time during conventional glass melting route promoted the search for alternative in developing new bioactive glass (BG) composition with improved in fabrication temperature and melting time. The current project involved fabrication of new BG compositions based on SiO₂-CaO-Na₂O-P₂O₅ system via melt derived route. It was confirmed that all bioactive glass composition can be melted at temperature lower than 1400 °C. Formation of Si-O-Si (tetrahedral) functional group highlighted that silicate based glass was established as detected by Fourier transform infrared spectroscope (FTIR). BG bioactivity was performed by incubating the BG powder in Tris-buffer solution (pH 8) for 7, 14 and 21 days. In vitro test confirmed the apatite formation on the bioactive glass surface upon soaking in Tris-buffer solution with characteristic of carbonate group (C-O) and P-O band noticed from FTIR and present of crystalline peak observed in X-ray diffraction (XRD). Morphology of apatite formation on BG surface was observed using scanning electron microscope (SEM).     

Synthesis,Characterization and Biological Evaluation of a New Sol-Gel Derived B and Zn-Containing Bioactive Glass: <Emphasis Type="Italic">In Vitro</Emphasis> Study

In this study we employed the sol-gel method to synthesize new CaO–P₂O₅–SiO₂–ZnO–B₂O₃ bioactive glasses. Three samples with various B₂O₃ content (5, 10 and 15 mol %) was prepared and their bioactivity were evaluated by immersion in simulated body fluid (SBF) and the glasses were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The experimental results revealed that with increasing the amount of boron content, a more crystalline domain can be observed in their XRD patterns and consequently the formation of hydroxyapatite (HA) increased. FTIR spectra showed that the sample containing 10 mol% of boron had the sharpest peaks attributed to the formation of hydroxyapatite. Biocompatibility of the samples was examined by MTT assay and alkaline phosphatase activity. The result ascertained that the synthesized bioactive glass had good biocompatibility and can serve as a bone substitute in bone defects.