The main purpose of the paper is the evaluation of the influence of chemical composition of the gel of the synthesized 15CaO?0.5P2O5-6SiO2 glass-ceramic on the structure, crystallization behaviour and in vitro bioactivity in static conditions for different periods of time - 3, 9 and 30 days in 1.5SBF. The obtained glass-ceramic was synthesized via polystep sol-gel technique. The structure of the prepared and the one thermally treated at 1200?C for 2 h powder was studied by XRD, 29Si MAS NMR, FTIR and SEM. .

Abstract:In this work we present experimental results about synthesis, structure evolution and in vitro bioactivity of new calcium phosphate silicate/wollastonite (CPS/W) glass-ceramics. The samples obtained were synthesized via polystep sol-gel process with different Ca/P+Si molar ratio (R). The structure of the materials obtained was studied by XRD, FTIR spectroscopy and SEM. XRD showed the presence of Ca 15 (PO 4 ) 2 (SiO 4 ) 6 , β-CaSiO 3 and α-CaSiO 3 for the sample with R=1.89 after thermal treatment at 1200°C/2h. The XRD results are in good agreement with FTIR analysis. SEM denotes that apatite formation can be observed after soaking in simulated body fluid (SBF). © Versita Warsaw and Springer-Verlag Berlin Heidelberg.

In this work we present the experimental results on synthesis structure and in vitro bioactivity of collagen (C)/calcium phosphate silicate (CPS)/chondroitin sulfate (ChS) composites with C/CPS ratio of 25:75 wt. % and 75:25wt. %. The synthesized composites were characterized by XRD, FTIR and SEM/EDS. XRD and FTIR before in vitro test proved that the carbonate containing hydroxyapatite (CO 3 HA) formed in situ. After in vitro test for 3 days in 1.5 SBF, the nucleation of B-type CO 3 HA was estimated on the obtained C/CPS=75:25 wt. % composite with cauliflower-like assembly. On the C/CPS=25:75 wt. % amorphous hydroxyapatite (HA) layer was observed.

The main purpose of the presented article is the preparation of novel glass-ceramics in CaO-SiO 2 -P 2 O 5 -MgO system and evaluation of carbonate apatite formation after soaking in TRIS-HCl buffer solution for 14 days. The investigated samples were prepared via sol-gel method and structure of the obtained samples was studied using XRD, FTIR, SEM, XPS and ICP-AES. XRD of the thermally treated samples showed that the presence of some crystalline phases is depended on the gel composition. FTIR revealed the existence of all characteristic bands for the observed crystalline phases. SEM monitored the presence of particles with different morphology. After soaking in TRIS-HCl solution, FTIR confirmed that carbonate apatite was formed on the soaked surface. The obtained data are in a good agreement with XPS analysis. The change of ions concentrations in TRIS-HCl buffer solution after immersion of the prepared glass-ceramics was recorded by ICP-AES measurements.

Abstract: