HYDROXYAPATITE/GEMOSIL NANOCOMPOSITE

Bone is a lightweight but relatively stiff and tough material providing the structural framework for all vertebrates. Previously, a hydroxyapatite-gelatin nanocomposite system (HAP-GEL) was developed to resemble the composition and ultrastructure of natural bone for the application of tissue engineering(2). In the current study, the purpose was to improve the formability of HAP-GEL using silane chemistry. The new hydroxyapatite/GEMOSIL (gelatin modified silane) consists of the following major components: HAP-GEL in the form of colloids, and silica matrices of aminosilane that bind strongly to both HAP and gelatin through covalent and ionic interactions. Various proportions of HAP-GEL and silane were parametrically investigated to optimize the properties of HAP/GEMOSIL. It was found that the setting time of the new HAP/GEMOSIL was approximately five times shorter than that of HAP-GEL; the material was resistant to erosion in aqueous solution after setting. Other advantages of HAP/GEMOSIL include low shrinkage, high ductility and good compressive strength. The salt-leaching method can be applied to create porous scaffolds of HAP/GEMOSIL. The preliminary tests showed that the compressive strength of porous HAP/GEMOSIL had sufficient strength to support reconstruction of bony defects. Cell culture, using MC3.T3-E1, showed excellent proliferation and differentiation. In conclusion, HAP/GEMOSIL appeared to retain the properties of HAP-GEL; in addition, it offered superb Forming ability for scaffolding of tissue engineering.