Bioactive glass is an emerging research area for many scientists around the world. A large processing window combined with high bioactivity are anticipated features for such kind of glass. In fact, both features depend upon the glass network connectivity (NC). A good bioactive glass has a network that ensures a balance between the processing properties and the bioactivity. This study aims at developing a new chemical composition based on that of ICIE16 bioactive glass. Therefore, new compositions were investigated by introducing boron oxide and magnesium oxide with different molar ratios ranging from 1 to 3 mol% each to the composition of ICIE16; In addition,Na2O was partially replaced by P2O5. Melt-quenching technique was followed to prepare the bioactive glass. So far, the results have shown that the processing window increases with the proposed modifications. BP3 and BM2 bioactive glasses show the maximum processing window of a round 250 K. The relationship between the chemical composition and the processing window as well as the corresponding bioactivity will be hereafter discussed.

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The pure hydroxyapatite (HAp) and antibacterial co-doped hydroxyapatite [(Cu, Mg) HAp] nano-powders were synthesized by Wet chemical precipitation method. Calcium hydroxide (CaOH 2 ) and phosphate acid (H 3 PO 4 ) were utilized as starting materials, magnesium oxide (MgO) and copper oxide (CuO) represent the doping elements . The ratio (Ca/P) kept at 1.67 and PH value maintained to10 at room temperature. Pure HAp [Ca 10 (PO 4 ) 6 OH 2 ] and three stoichiometric compositions of the codoped HAp were prepared which were [(Mg 0.25 ,Cu 0.75 )Ca 9 (PO 4 ) 6 OH 2 ],[(Mg 0.5 ,Cu 0.5 )Ca 9 (PO 4 ) 6 OH 2 ] and [(Mg 0.75 ,Cu 0.25 )Ca 9 (PO 4 ) 6 OH 2 ]. All the prepared powders were calcinated at 800 °C for 2hrs . The structure, antibacterial activity, and toxicity with cell viability have been investigated using several characterization techniques . XRD results showed that the fabricated undoped-HAp and co-doped HAp has one (hexagonal) phase , and the FT-IR results shows functional group that confirm the results of XRD. The TEM images indicated that incorporation of Cu 2+ and Mg 2+ has altered the size and morphology of the resulting HAp crystals which appears elongated with dissimilar sizes. Antibacterial test indicated that co-doped HAp [(Mg 0.25 ,Cu 0.75 )Ca 9 (PO 4 ) 6 OH 2 ] showed high activity versus E.coli and S.aureus bacteria. The MTT assay for the [(Mg 0.75 ,Cu 0.25 )Ca 9 (PO 4 ) 6 OH 2 ] has shown superior positive role on cell viability as appears in the fluorescent image, and has acceptable antibacterial activity.

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