Preparation of mechanically competent, bioactive, and bioresorbable nanocomposite foams for biomedical applications A review on nanostructur

This work successfully synthesized highly porous, mechanically competent, bioactive, and bioresorbable nanocomposite foams on addition of bioactive glass (BG) to pure hydroxyapatite (HA). Nanocomposite foams were prepared on addition of 63S BG to pure HA, in proportion of 0, 25, 50, 75, and 100 wt.%, and their mechanical properties and bioactivity were compared. The results showed that the nanocomposite foams have a grain size in the range 24-38 nm and pore size in the range 100-400μm. The compressive strength measurements showed that the compressive strength and elastic modulus increased with increasing the amount of BG addition up to 25 wt.% and then decreased by more addition of BG. In comparison to results of other researchers, the foams compressive strength has increased with decreasing the particle size to nano scale and production of BG reinforced HA. The maximum values of compressive strength and elastic modulus of prepared foams were found to be about 2.78 MPa and 219 MPa, respectively. The mean values of true (total) and apparent (interconnected) porosity were calculated in the range 84-88% and 57-76%, respectively. The high specific surface area of the prepared foams (40.65 m2.g−1), due to the high porosity level (84-88%) and nanosized structure (24-38 nm), increases the rate of bioresorbability and accelerates the deposition process of bone-like apatite, which aids bone repair and fixation. In vitro tests showed that by increasing the amount of BG, the bioactivity and amount of bone-like apatite formedin dependence of immersion time in SBF increased and more pores were filled. The obtained composite foams have chemical composition similar to the mineral phase of bone and by changing the ratio of HA/BG it can reach the appropriate bioactivity and biodegradability level needed for different biomedical applications.

کلیدواژه ها:

Nanocomposite ، Foams ، Bioactive glass ، Hydroxyapatite ، Gelcasti