摘要
Mesoporous bioactive glasses(MBGs)are promising materials for regenerative medicine,due to their favorable properties including bioactivity and degradability.These key properties,but also their surface area,pore structure and pore volume are strongly dependent on synthesis parameters and glass stoichiometry.However,to date no systematic study on MBG properties covering a broad range of possible compositions exists.Here,24 MBG compositions in the SiO_(2)-CaO-P_(2)O_(5) system were synthesized by varying SiO_(2)(60-90 mol%),CaO and P_(2)O_(5) content(both 0 to 40 mol-%),while other synthesis parameters were kept constant.Mesopore characteristics,degradability and bioactivity were analysed.The results showed that,within the tested range of compositions,mesopore formation required a molar SiO_(2) content above 60%but was independent of CaO and P_(2)O_(5) content.While mesopore size did not depend on glass stoichiometry,mesopore arrangement was influenced by the SiO_(2) content.Specific surface area and pore volume were slightly altered by the SiO_(2) content.All materials were degradable;however,degradation as well as bioactivity,i.e.the ability to form a CaP mineral on the surface,depended on stoichiometry.Major differences were found in early surface reactions in simulated body fluid:where some MBGs induced direct hydroxyapatite crystallization,high release of calcium in others resulted in calcite formation.In summary,degradation and bioactivity,both key parameters of MBGs,can be controlled by glass stoichiometry over a broad range while leaving the unique structural parameters of MBGs relatively unaffected.This allows targeted selection of material compositions for specific regenerative medicine applications.
基金
This work was supported by the Alexander von Humboldt Foundation(Germany)
This research has been in part made possible with the support of the Dutch Province of Limburg(LINK project).PH gratefully acknowledges the Gravitation Program‘Materials-Driven Regeneration’(024.003.013),funded by the Netherlands Organisation for Scientific Research.
