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In this work, we studied simultaneous effect of gamma irradiation and SrO substitution for Na O on bioactivity, cytotoxicity and antimicrobial properties of 45S5 glass. Gamma irradiation was mainly introduced in this work as an effective sterilizing technique, improvement of bulk properties and surface modification of glass. Where, gamma irradiation is considered a modifier for glass network due to generation of defects resulted from this irradiation. Furthermore, SrO was introduced into the glass structure in place of Na O in order to reduce a probable toxic effect of Na O for surrounding tissue by decreasing its percentage. Where, Sr is characterized by its antibacterial properties, as well as, it induces formation of bone tissue and inhibits its resorption. The cell viability was studied for selected samples using Vero cells. As well as, antimicrobial activity was evaluated against Bacillus subtilis, Staphylococcus pneumonia, and Escherichia coli and Pseudomonas aeruginosa bacteria. The results showed that substitution of Na O by SrO in glass composition decreased the glass dissolution in SBF. However, the glass dissolution increased after irradiation of such glass due to generation of nonbridgingoxygens (NBOs) throughout glass network by gamma irradiation, and this effect was more obvious for Sr-contained glass. On the other hand, two selected Sr-containing glasses (gamma irradiated at 0 and 25 kGy) showed a good ability to stimulate cell proliferation of normal fibroblast cells, as well as, they represented a potential ability to inhibit the growth of or kill bacteria, which is considered an important issue commonly found in a clinical situation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1646-1655, 2017.

A series of bioglass (BG) reinforced composite scaffolds based on polyvinyl alcohol and Gelatin were prepared using g-radiation as clean source of initiation and crosslinking. To evaluate the potential applicability of the obtained reinforced BG composites as a scaffold for bone tissue regeneration, the in vitro apatite-forming ability was assessed in simulated body fluid. The formation of apatite layer was confirmed using different techniques including Fourier transform spectroscopy technique, X-ray diffraction, and scanning electron microscopy. In addition, gel fraction, swelling behavior, and thermal properties using thermogravimetric analysis technique of the composite scaffolds were investigated. The obtained data revealed that the presence of the BG particles entrapped within the scaffold matrix promotes hydroxyapatite formation, as a function of immersion time. The degradation of the reinforced composites in phosphate buffer was studied by measuring their weight loss as well as changes in the pH of the incubating medium as a function of time and BG content. In vitro release of ketoprofen as anti-inflammatory and analgesic drug was investigated to evaluate the composite scaffolds potential as drug carrier. The obtained results showed that the ketoprofen loaded scaffolds were able to deliver the loaded drug in a sustainable manner that last for about 144 h. POLYM. COMPOS., 39:606-615,