Development of calcium phosphate cement composed of silica-modified hydroxyapatite, cerium oxide, and silica as an osteoporotic bone filler.

Calcium phosphate cement (CPC), composed of silica-modified hydroxyapatite (HA-SiO 2), cerium oxide (CeO 2), and silica (SiO 2), was developed as an osteoporosis bone filler. The effect of CeO 2 and SiO 2 content on the CPC's properties, such as crystal parameters, surface properties, antibacterial activity, and toxicity properties, were studied. HA-SiO 2 was prepared using the sol-gel method, while CeO 2 was prepared using the precipitation method. HA in HA-SiO 2 has crystal properties similar to pure HA. Synthesized CeO 2 contains Ce3+ and Ce4+ ions with Ce3+/Ce4+ = 0.34. Computational calculation predicted that the CeO 2 (111) surface and glycine molecule interaction was categorized as chemisorption. Moreover, CeO 2 has antibacterial activity toward Escherichia coli and Staphylococcus aureus. Combining HA-SiO 2 and CeO 2 did not change the adsorption-desorption isotherm curve type, but slightly decreased the surface area, total pore volume, and average pore. Increasing the percentage of CeO 2 and adding 10 % SiO 2 (w/w) affected the particle's size and CeO 2 distribution. However, CPC lost antibacterial activity toward Staphylococcus aureus but adding 10 % SiO 2 (w/w) increases the bacterial activity toward Escherichia coli close to that of pure CeO 2. The MTT assay using pre-osteoblast MC3T3E1 cells showed that the CPC has IC 50 = 4227 μg/ml or is nontoxic. [Display omitted] [ABSTRACT FROM AUTHOR]