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Recently, most researchers have been focusing on the development of the mesoporous bioactive glasses for medical application. These materials are capable for bone tissue (soft and hard) regeneration and the delivery of bio-responsive active therapeutic molecules such as drug, proteins, nucleic acids, and peptides. However, the structure properties of the mesoporous bioactive glass are easily been controlled with a small change of calcination temperature during the sample preparation. In this perception, a series of mesoporous borosilicate bioactive glasses (MBBGs) with the composition of 10B2O -70SiO2 -15CaO- 5P2O5 were prepared using the combination of sol-gel and evaporation induced self-assembly (EISA) and characterised. The calcination temperature of the bioactive glass preparation was controlled with varied temperature of 400°C, 500°C, 600°C and 700°C. The amorphous nature of the prepared samples were confirmed using XRD pattern. The EDX and FTIR spectra shows a small amount of carbon trapping inside the sample is increases with the increased of calcination temperature. All MBBGs samples show a ratio of Si-O-NBO and Si-O-Si (sym) bigger than 1. It is established that the structure of the mesoporous borosilicate bioactive glass can be tailored by controlling the calcination temperature.

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Neutron diffraction, 27 Al MAS NMR, and 27 Al Double Quantum MAS NMR results are presented and analyzed to determine the local environments of the cations in a series of aluminum tellurite glasses. Total scattering results show that, within a maximum Te−O distance of 2.36 Å, tellurium exhibits a mix of [TeO 3 E] and [TeO 4 E] environments (E = electron lone-pair), with a linear reduction in the average tellurium−oxygen coordination number as Al 2 O 3 is added to the glass. This is accompanied by a linear decrease in the average aluminum−oxygen coordination number as [AlO 4 ] units form at the expense of [AlO 6 ] units, while the fraction of [AlO 5 ] units remains roughly constant. A consideration of the bonding requirements of the five structural units in the glass, [TeO 3 E], [TeO 4 E], [AlO 4 ], [AlO 5 ], and [AlO 6 ], has allowed a direct quantitative relationship between tellurium−oxygen and aluminum− oxygen coordination numbers to be derived for the first time, and this has been successfully extended to the boron tellurite system. Double Quantum 27 Al MAS NMR indicates that, in contrast to previous reports, the shortest Al...Al separations are significantly smaller (∼3.2 Å) than expected for a uniform distribution and there is a preference for [AlO 6 ]−[AlO 6 ] and [AlO 4 ]−[AlO 4 ] corner sharing polyhedra. These associations support a new structural model which successfully applies the principle of charge balance to describe the interaction of tellurium and aluminum and identifies and explains the clustering of [AlO n ] polyhedra in the glass and their preferred associations. [AlO 6 ] and [TeO 4 E] units dominate the network in TeO 2 -rich glasses and [AlO 4 ] − units form to stabilize the [TeO 3 E] + units as alumina is added to the glass.