resumo
An alkali-free series of bioactive glasses has been designed and developed in the glass system CaO-MgO-SiO(2)-P(2)O(5)-CaF(2) along the diopside (CaMgSi(2)O(6))-fluorapatite (Ca(5)(PO(4))(3)F)-tricalcium phosphate (3CaO center dot P(2)O(5)) join. The silicate network in all the investigated glasses is predominantly coordinated in Q(2) (Si) units, while phosphorus tends to remain in an orthophosphate (Q(0)) environment. The in vitro bioactivity analysis of glasses has been made by immersion of glass powders in simulated body fluid (SBF) while chemical degradation has been studied in Tris-HCl in accordance with ISO-10993-14. Some of the investigated glasses exhibit hydroxyapatite formation on their surface within 1-12 h of their immersion in SBF solution. The sintering and crystallization kinetics of glasses has been investigated by differential thermal analysis and hot-stage microscopy, respectively while the crystalline phase evolution in resultant glass-ceramics has been studied in the temperature range of 800-900 degrees C using powder X-ray diffraction and scanning electron microscopy. The alkaline phosphatase activity and osteogenic differentiation for glasses have been studied in vitro on sintered glass powder compacts using rat bone marrow mesenchymal stem cells. The as-designed glasses are ideal candidates for their potential applications in bone tissue engineering in the form of bioactive glasses as well as glass/glass-ceramic scaffolds. Published by Elsevier Ltd. on behalf of Acta Materialia Inc.
palavras-chave
SIMULATED BODY-FLUID; IN-VITRO; MECHANICAL-PROPERTIES; CERAMICS; 45S5; BEHAVIOR; PH; CRYSTALLIZATION; BIOCERAMICS; DISSOLUTION
categoria
Engineering; Materials Science
autores
Goel, A; Kapoor, S; Rajagopal, RR; Pascual, MJ; Kim, HW; Ferreira, JMF
nossos autores
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)agradecimentos
The financial support from FCT-Portugal is highly acknowledged. Also, Saurabh Kapoor is thankful to CICECO and University of Aveiro for the research scholarship. Partial supports from the National Research Foundation, Republic of Korea (Research Centers Program, Grant# 2009-0093829 and WCU Program, Grant# R31-10069) are also acknowledged.