Due to its excellent biocompatibility, bioactivity and osteo-conductivity, bioactive glass (BG) has become an interesting topic in tissue regeneration field Over the past decades. Herein, the fabrication of bioactive glass submicron fibers by employing an electrospinning process based on sol-gel is reported.Starting sol was prepared by mixing tetraethyl orthosilicate (TEOS), triethyl phosphate (TEP) and calcium nitrate tetrahydrate as precursors in an adequate solvent. Different amounts of poly (vinyl alcohol) (PVA) was used in order to investigate the polymer content effect on fibers. Furthermore, electrospinning parameters such as voltage and working distance were optimized. The lowest average fiber diameter was obtained at PVA/BG sol ratio of 8: 4, voltage and working distance of 20 kV and 10 cm respectively, which is reported as optimized sample (0.991 μm before and 0.7 μm after calcination).After the heat treatment and de-polymerization, structural characterizations were done. XRD pattern and FT-IR spectrum revealed the presence of bioactive glass. Results indicated that the fibers diameter and homogeneity were reduced after calcination and showed an intensification by increasing polymer.

Background and aims: The presence of an appropriate scaffold at the wound site could significantly improve the healing process. In this study, we aimed to prepare a biomimetic nanocomposite scaffold composed of chitosan, gelatin, and 58S bioglass nanoparticles for skin tissue engineering. Methods: The nanocomposite scaffolds composed of chitosan, gelatin, and 58S bioglass nanoparticles were fabricated through electrospinning process. Then the cell viability assay was performed in order to evaluate the biological properties of the membranes. The optimum concentration of bioglass nanoparticles was determined for further studies. In vitro characterization was also performed to evaluate physicochemical properties of the scaffolds. Results: The chitosan/gelatin scaffold containing 2% of 58S bioglass nanoparticles showed no cell toxicity, and the dermal fibroblasts were found capable of proliferation on the membrane. The in vitro results obtained from the scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and porosity tests demonstrated the appropriate properties of the membrane as a scaffold for skin regeneration. Conclusions: It was concluded that a chitosan-gelatin membrane containing 2% of 58S bioglass nanoparticles had the potential to function as a scaffold to accelerate wound healing due to its suitable properties, such as high porosity, high surface/volume ratio, and excellent biocompatibility.

Background: Bioactive glasses 58S, are silicate-based materials containing calcium and phosphate, which dissolved in body fluid and bond to the bone tissue. This type of bioactive glass is highly biocompatible and has a wide range of clinical applications. Methods: The 58S glass powders were synthesized via sol-gel methods, using tetraethyl orthosilicate, triethyl phosphate, and calcium nitrate, as precursors. Upon the analyses of phase and chemical structures of bioactive glass in different gelation times (12, 48, and 100 h), the appropriate heat treatment (at 525, 575, and 625 ° C) was performed to eliminate nitrate compounds and stabilize the glass powder samples. The in vitro assay in SBF solution revealed the bioactivity of the synthesized 58S glass through the morphological (SEM), chemical structure (FTIR), release of calcium, phosphorous and silicon elements, pH variations, and weight loss measurements. The behavior of MSCs in the presence of bioactive glass powders was studied by MTT cytotoxicity, cell staining, ALP activity and biomineralization tests, as well as by the evaluation of ALP, osteocalcin, osteonectin, collagen I, and RUNX2 gene expression. Results: The results confirmed a gelation time of 100 h and a calcination temperature of 575 ° C at optimal conditions for the synthesis of nitratefree bioactive glass powders. Conclusion: The glass spherical nanoparticles in the range of 20-30 nm possess the improved bioactivity and osteogenic properties as demanded for bone tissue engineering.

Background: In recent years, bioactive bioceramics such as bioglass and hydroxyapatite (HA) have been introduced as a remarkable development in the field of medicine due to their bio-adaptability, non-toxicity, and persistence, in vivo. They have many potential applications in the repair of bone defects and hence they have attracted significant interest from scholars.Objectives: The aim of this study was to synthesize inorganic matrix CuO-based bioglasses and evaluate their antibacterial activity against aerobic bacterial infections in bone implants.Methods: Nano-composite samples of silica-based bioactive glass, 60SBGwith nano-powderCuO, were synthesized using the sol-gel method and then assessed with regard to their antibacterial properties againstStaphylococcus aureus using well diffusion agar. The samples included BG58S (58%SiO2, 36%CaO, 6%P2O5), BG/10CuO (58%SiO2, 26%CaO, 6%P2O5, 10%CuO), and BG/20CuO (48%SiO2, 26%CaO, 6%P2O5, 20%CuO). To evaluate their bioactivity, the prepared samples of BG/20CuO, BG/10CuO, and BG58S were immersed in simulated body fluids (SBF). The surface morphology and structure of the samples before and after immersion in the SBF were characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR), respectively. Then, the BG/20CuO and BG/10CuO samples were loaded in clindamycin, an antibiotic widely used in the treatment of osteomyelitis, and their release profiles were studied in phosphate buffer solution.Results: It was observed that the growth inhibition zone increased through clindamycin release due to the increasing CuO percentage in the nanocomposite of bioactive glass. The bioactivity of the nanocomposite/bioglass with CuO was superior to that of bioglass alone. In this study, the BG/20CuO sample showed a sustained release of clindamycin, which is sufficient for a drug delivery system.Conclusions: Increasing the Cu nanoparticles in bioactive glass samples leads to the release of Cu2+, which has a positive effect on the antibacterial mechanism, as well as decreasing the culturedStaphylococcus colonies found on the bioglasses. Therefore, it seems that the nanocomposite/bioglass of CuO is a promising option for aerobic bacterial inhibitor systems in common bone implant infections.

Nowadays, zirconia has been favored greatly for dental implants; however its disadvantages such as poor mechanical properties and brittleness makes it unsuitable. On the other hand, bioactive glasses coating have been utilized on tougher substrates such as zirconia. Bioactive glass coatings can decrease the healing time and hence accelerate the formation of the bond between bone and implant. Hence, in this study, we introduce the novel zirconia/bioactive glass composites with high mechanical strength and bioactivity to achieve the ideal implant in dentistry. Furthermore, a review of bioactive glass coatings (i. e., 45S5 and 58S) on zirconia as well as surface modification methods (i. e., sol-gel, laser cladding, plasma spraying, etc. ) is provided.