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The research aimed to evaluate the mechanical behaviour, hybridisation and osteoblast activities of novel baghdadite/PCL-graphene nanocomposite scaffold. The mechanical behaviour was examined via measuring the compressive strength and Young's module, the hybridisation was evaluated by Fourier transform infrared spectroscopy, Raman spectroscopy, and Brunauer Emmet Teller, and the osteoblast activities were assessed via MG-63 osteoblast cells. The results rendered PCL as a significant factor to enhance the mechanical strength of ceramic scaffolds. Due to the existence of σ and π covalent bonds in its structure, hydrophilicity and biocompatibility, graphene could be applied in scaffolds' chemical compound to greatly enhance their mechanical and biological behaviours. This scaffold indicated compressive strength and Young's module higher than 2 MPa and 0.05 GPa. Regarding cell behaviours, MG-63 osteoblast cells spread and attached well on the scaffolds confirming the viability, cytotoxicity, excellent cell attachment and proliferation. The results indicated that this scaffold possesses outstanding potential as a temporary substrate for bone tissue engineering. [ABSTRACT FROM AUTHOR]

This research aimed at fabrication of baghdadite scaffolds with chitosan coating via combining of polymeric sponge replication and dip-coating methods with improved mechanical and biological properties. The composite was characterized using x-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Porosity, compressive strength, in vitro bioactivity and biological responses of human bone marrow mesenchymal stem cells were evaluated. The porosity percentage and compressive strength values were 79 ± 0.87 and 2.88 ± 0.34, respectively. The results showed chitosan coating could largely enhance the mechanical strength of baghdadite scaffolds. Also apatite-like layer formation was observed. Based on the MTT assay and SEM micrographs, human bone marrow mesenchymal stem cells were spread and attached well on the surface of the scaffold, which indicated a high biocompatibility. The results showed that this composite scaffold has the potential to be used as a temporary substrate for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Background. Glass ionomer cements are one of the most important restorative materials in dentistry. One of the disadvantages of glass ionomer cements is their undesirable mechanical properties and bioactivity. Aim. The aim of this work was preparation and characterization of strontium-containing glass ionomer cement and evaluation of its bioactivity in the simulated body fluid. Materials and Methods. The ceramic component of glass ionomer cement was made by melting method. Scanning electron microscope (SEM) was used to study the size and the shape of glass particles. In order to determine the phase combination in the produced material, X-ray diffraction (XRD) analysis was carried out. The chemical composition of the glass was evaluated by X-ray florescence (XRF), and the surface area of the particles was determined using BET method. In order to investigate the biological properties of the glass, samples were immersed in simulated body fluid (SBF). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to recognize and confirm the apatite layer on the composite surface. Results and Conclusions. The result of X-ray diffraction (XRD) analysis confirmed the glassy structure of the produced ionomer cements.The result of XRF confirmed the presence of Sr in the chemical composition. Fourier transform infrared spectroscopy test and electron microscope confirmed the formation of apatite layer on the surface of material. The final result of this research was gaining glass ionomer cement containing Sr with improved bioactivity. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work was to produce and characterize SiO2–CaO–P2O5 bioactive glass nanoparticles with negative zeta potential for possible use in biomedical applications. 63S bioactive glass was obtained using the sol–gel method. X-ray fluorescence (XRF) spectroscopy and dispersive X-ray analysis (EDX) confirmed the preparation of the 63S bioactive glass with 62.17% SiO2, 28.47% CaO and 9.25% P2O5 (in molar percentage). The in vitro apatite forming ability of prepared bioactive glass was evaluated by Fourier transform infrared spectroscopy (FTIR) after immersion in simulated body fluid (SBF). The result showed that high crystalline hydroxyapatite can form on glass particles. By the gas adsorption (BET method), particle specific surface area and theoretical particle size were 223.6±0.5m2/g and ∼24nm, respectively. Laser dynamic light scattering (DLS) indicated particles were mostly agglomerated and had an average diameter between 100 and 500nm. Finally, using laser Doppler electrophoresis (LDE) the zeta potential of bioactive glass nanoparticles suspended in physiological saline was determined. The zeta potential was negative for acidic, neutral and basic pH values and was −16.18±1.8mV at pH 7.4. In summary, the sol–gel derived nanoparticles revealed in vitro bioactivity in SBF and had a negative zeta potential in physiological saline solution. This negative surface charge is due to the amount and kind of the ions in glass structure and according to the literature, promotes cell attachment and facilitates osteogenesis. The nanometric particle size, bioactivity and negative zeta potential make this material a possible candidate for bone tissue engineering. [Copyright &y& Elsevier]

Bioactive glasses represent a class of attractive materials in bone reconstruction. This study describes the detailed preparation and characterization of a silicate-based bioactive glass-ceramic (R-SBgC). Synthesis of bioactive glasses using the sol–gel method has advantages compared to the melting method. However, expensive raw materials are required and pose a major issue. To overcome this, R-SBgC was synthesized via the sol–gel method using Rice Husk (RH) as a natural silica precursor. The RH was heat treated and used as an alternative to tetraethyl orthosilicate (TEOS), which is a common synthetic silica precursor. X-ray diffraction (XRD), X-ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) were used to characterize the rice husk ash (RHA). The findings reveal that the extracted silica has a high purity (~ 99%). The synthesized R-SBgC powder was characterized using SEM, Energy Dispersive X-ray Analysis (EDX), XRD, XRF and Fourier-Transform Infrared Spectroscopy (FTIR) to complete the morphological and elemental analysis. Moreover, in vitro bioactivity via an immersion assessment was conducted for up to 14 days. The HA layer formation, which is an indicator of the bioactivity on the surface of the R-SBgC, was confirmed using SEM, EDX and further by FTIR. Biocompatibility of the R-SBgC was evaluated in vitro. After 3 days of human bone marrow stromal cell (hBMSC) seeding, SEM analysis revealed cell attachment on the surface of the R-SBgC. Alamar blue and XTT cytotoxic assays demonstrated cell proliferation abilities and the non-cytotoxic effect of the R-SBgC. Altogether, the results demonstrate that prepared rice husk-derived bioactive glass ceramic may be a promising carrier for tissue engineering applications. [ABSTRACT FROM AUTHOR]