The aim of this study was to propose and validate a new unified method for testing dissolution rates of bioactive glasses and their variants, and the formation of calcium phosphate layer formation on their surface, which is an indicator of bioactivity. At present, comparison in the literature is difficult as many groups use different testing protocols. An ISO standard covers the use of simulated body fluid on

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Organic–inorganic hybrid materials composed of co-networks of biodegradable polymer and silica have potential to combine the properties of an elastic organic polymer and inorganic silica. The nanoscale interaction of the co-networks and formation of covalent bonds between them are expected to provide tailored mechanical properties and congruent degradation. Alginate is a natural polymer commonly used in tissue engineering applications due to its good biocompatibility and biodegradability. In this work we present new alginate–silica hybrids prepared through nucleophilic ring opening reaction of 3-glycidoxypropyl trimethoxysilane (GPTMS) by carboxylic groups of alginate and incorporation of this functionalized alginate into the sol–gel process to make a hybrid. The role of the GPTMS is to provide organic/inorganic covalent coupling. The reaction of alginate with GPTMS was followed using NMR, FTIR and ToF-SIMS and the dissolution behaviour, bioactivity and mechanical properties of the resultant alginate–silica hybrid monoliths were evaluated. While mechanical strength was high with values of 110–242 MPa comparable to that of cortical bone, the amount of GPTMS coupling to the alginate was low, with the rest of the GPTMS forming diols or a separate network

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Sol-gel-derived SiO 2 -CaO-P 2 O 5 porous glass monoliths with a dual hierarchical pore structure including both macropores of B20-200 micrometers and mesopores B5-20 nanometers in size are prepared in the presence of the drying control chemical additive formamide, for a possible application as scaffolds in bone tissue regeneration. While the mesopores are intrinsic to the sol-gel processing, the interconnected macropores are achieved through a polymer-induced phase separation together with the sol-gel transition, by adding a water-soluble polymer, poly(ethylene oxide), to the precursor sol. The textural nanopore structure is controlled through solvent exchange procedures and the addition of urea. The overall pore size distribution obtained by mercury intrusion porosimetry was found to shift to larger pore sizes when formamide is added. In vitro tests are used to evaluate the bioactivity. The cell-support function of the resultant scaffolds is also assessed in vitro using osteoblast-like cells cultured for 2 days. The results show that the scaffold has a significant bioactivity and a good ability to support the attachment of MC3T3 preosteoblast cells.