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Template directed synthesis of nano-structured bioceramics [thesis]

Yufeng Zhao
In the past few years, mesoporous structures have gained great attention for their applications such as catalyst, electronic materials and sensors etc. However, it is noted that the formation and control of pore size distribution remain to be a challenging area to date. Among the many approaches to form various meso-structures, tremendous interest has been placed on surfactant-based templating synthesis. A particular direction templating of meso-structures through the use of surfactants
more » ... surfactants self-assembly, as exemplified through the development of meso-structured silica and their variants was synthesized. In the present work, novel hexagonal-ordered {P6mm) mesoporous bioactive glasses have been successfully synthesized using block copolymer Pluronics F127 and PI23 as surfactant. Mesoporous hydroxyapatite-silica composite materials with different Si:Ca:P ratio, as well as mesoporous hydroxyapatite have been synthesized for the first time, using block copolymer Pluronics P123 as surfactant. To explain the microbehaviour during the formation of mesoporous structure, the probable mechanisms have been proposed. Synchrotron in situ small angle x-ray diffraction study has been carried out for the first time on the mesoporous bioactive glasses and experimentally verified the proposed mechanism, which indicated that the systems go through a complicated phase transformation, from a disordered to a finely ordered hexagonal structure during the self-evaporation process. In vitro drug delivery property of the synthesized mesoporous materials has been systematically studied using a model drug metroclopromide. The P123 templated mesoporous bioactive glasses present significantly higher loading and better sustained release compared to other samples, which could be attributed to their higher pore volume and surface area.
doi:10.32657/10356/35961 fatcat:yswecqiutnat7fajshk5w47xwm