Properties Of Bioglass Research Articles

Bioactive glasses enriched with zinc and strontium: synthesis, characterization, cytocompatibility with osteoblasts and antibacterial properties.

Purpose: The aim of the presented work was to characterize the new obtained bioglasses and assess their biological performance in vitro. Bioglasses were produced using the sol-gel method in the SiO2-P2O5-CaO system, for the purpose as composite ingredients. Their chemical composition was enriched with ZnO to introduce antibacterial properties and SrO with osteoinductive effect. The properties of bioglasses were compared and the effect of chemical composition and particle size on their biological properties was assessed. Methods: The bioglasses were evaluated via TG-DTA, FTIR, SEM-EDS analyses before and after incubation in SBF solution. LDH and WST-1 tests were used to determine the level of cytotoxicity of the tested bioglasses on hFOB1.19 osteoblasts. Results: The results show that the developed bioglasses release Ca2+, are bioactive in SBF solution, not cytotoxic and show antibacterial activity in contact with Pseudomonas aeruginosa and Staphylococcus aureus strains. Bioglasses enriched with ZnO show the highest bactericidal activity. All tested bioglasses enhanced hFOB 1.19 cells proliferation. Particle size has a lower effect on biological performance of the bioglasses than their chemical composition. Conclusions: The conducted research showed that bioglass modification with SrO and ZnO can be considered particularly for the development of biomaterials supporting bone regeneration and the treatment of infected bone defects.

Natural rubber–based composites filled with bioglasses from a CaO‐SiO2‐P2O5‐Ag2O system. Effect of Ag2O concentration in the filler on composite properties

Bioactive glass was first synthesized by L. Hench in 1971. There are many studies on the properties of several metals and metal ions dopants used in the SiO2‐CaO‐P2O5 system of bioglasses, such as Ag, Cu, Zn, and Fe. A number of authors have carried out research related to the influence of silver oxide on the properties of bioglasses. However, publications on the properties of elastomer‐based composites containing bioactive glasses are relatively scarce. We have not found in the literature studies discussing how silver oxide concentration in bioglasses of the CaO‐SiO2‐P2O5‐Ag2O system affects the significant properties of a natural rubber biocomposite. In this regard, the purpose of the present work is to investigate the aforementioned influence on the properties of this type of composites, namely, vulcanization, physicomechanical, thermal, dynamic, dielectric, electric, and thermoconductive characteristics. We have established those parameters of the composites to be impacted considerably by both degree of filling with bioglass and the silver oxide content in the latter. The improvement in the composites thermostability and some of their physicomechanical performance is the most significant. The volume resistance decreases, and the thermal conductivity coefficients increase. Results from scanning electron microscopy and energy‐dispersive X‐ray (EDX) analyses have confirmed the influence of silver oxide initially on the phase composition of the bioglass, hence on the properties of the biocomposites through changes in the bioglass used as filler. The dielectric characteristics of some of the biocomposites suggest that they can be used as substrates and insulating layers in flexible antennas for short‐range wireless communications.

Effect of Leaching Agent Composition on Morphology, Thermal and Mechanical Properties of Bioglass® Reinforced Polyurethane Scaffold

Effect of Leaching Agent Composition on Morphology, Thermal and Mechanical Properties of Bioglass® Reinforced Polyurethane Scaffold

Mixed alkali effects in Bioglass® 45S5

Bioactive glasses, particularly Bioglass® 45S5, have been used to clinically regenerate human bone since the mid-1980s; however, their high crystallisation tendency still limits their range of applications. In order to develop new bioactive glass compositions, which combine high bioactivity with good processing of the melt, a deeper understanding of the role of modifier oxides on the structure and thermal properties of the glasses is required. Here, the influence of different alkali cations, Li2O, Na2O and K2O, on the properties of Bioglass® 45S5 has been investigated. Potassium cations expanded the silicate network, making it less compact, and thereby lowered hardness and Young's modulus. Lithium cations, on the other hand, made the silicate network more compact, which increased both hardness and Young's modulus. Structural analyses suggest non-random partitioning of modifier cations between the silicate and orthophosphate phase in mixed-alkali compositions. Transition and crystallisation temperatures of glasses containing two alkali cations showed the typical mixed alkali effect, with temperatures being lower than those of glasses containing one alkali cation only. Substitution of Na for Li or K resulted in an increased processing window (temperature range between Tg and the onset of crystallisation) with the exception of the fully substituted potassium glass, which had the smallest processing window of all glasses. Taken together, these results suggest that bioactive glasses in which sodium is partially substituted (particularly with potassium) are of great interest to improve the processing, making the glasses more suitable for sintering or fibre drawing applications.

Influence of Exposure for Gamma and X-Ray Radiation on Bioglass Reparative Material Measured Using Two Techniques

Bioglass is a material which can repair damaged living tissues and organs by interacting with biological systems. Bioglass were irradiated by different beam qualities (gamma and X-ray). The effectiveness of different doses and energies of gamma ray and X-ray were studied on bioglass as well as some dosimetric properties of bioglass were studied by applying the thermoluminescence technique and spectrometer technique. Results showed that the efficiency of electron and hole center generation depends on basic bioglass composition and also dependent on the type of ionizing radiation. The response of dose is not effective at working voltage 70 kV which means that the bioglass may be safe under this value of applied volt.

Mixture designs applied to glass bioactivity evaluation in the Si–Ca–Na system

Abstract Two mixture designs, permitting the reduction of experiment number, are applied to the SiO2–CaO–Na2O system in order to study two properties of bioglasses: bioactivity and HCA layer thickness. Samples are composed of 42–55% SiO2, 13.5–48% CaO and 10–35% Na2O. The bioactivity is studied with Fourier transform infra red spectroscopy (FTIR) and the thickness of HCA layer is measured with the help of scanning electron microscopy coupled with energy dispersive spectroscopy (SEM–EDS). The aim of this work is to correlate these two properties with the composition of glasses, establishing mathematical formulas. Several domains of interesting glasses were obtained, some of them with a fast reaction time, others developing a thick HCA layer. Some compositions, seeming to be more interesting than Hench’s 45S5, could have been pointed out.