Résumé:
This study initially focused on synthesizing diopside (CaMgSi2O6) using the solid-state
sintering method, starting with locally sourced dolomite (CaMg(CO3)2) and low-cost laboratory-
grade silicon dioxide (SiO2). The preparation process was carried out at a temperature of 1250°C
for two hours through two mechanisms: one without additives and the other with the addition of
0.5% sodium carbonate. The sintered samples were characterized using X-ray diffraction (XRD)
and Fourier-transform infrared spectroscopy (FTIR). Results demonstrated an improvement in
crystallization and sintering behavior with the addition of sodium carbonate (Na2CO3) , reflecting
enhanced sintering performance. It was also confirmed that sodium was incorporated into the
diopside without forming any secondary phases (Bioactive glasses).
Following the synthesis, the samples were crushed and subjected to bioactivity testing. This
evaluation involved immersing diopside granules in simulated body fluid (SBF) for varying
durations to examine the initiation and growth of apatite on their surfaces. The effect of sodium
carbonate (Na2CO3) on the biological properties of diopside was investigated by analyzing the
chemical composition using FTIR after immersion periods of 4 hours, 1 day, 4, 7, and 11 days.
The findings indicated distinct differences in the partial dissolution behavior of the diopside
granules during the early stages of immersion between samples with and without sodium
carbonate addition. This variability was attributed to the role of sodium cations as network
modifiers, reducing surface resistance to degradation in physiological fluids. Consequently,
sodium addition significantly enhanced apatite nucleation and accelerated the formation of
carbonate hydroxyapatite layers on sample surfaces compared to those without additives.
Furthermore, the samples containing sodium carbonate exhibited greater apatite deposition
compared to pure diopside counterparts. Therefore, the study concluded that sodium carbonate
acts as a bioactivity enhancer in diopside, improving their biological performance, particularly in
terms of bioactive properties.
