Organic-inorganic hybryd hydrogel microbeads for rapid bone formation

This paper describes a rapid bone tissue fabrication using chemically modified collagen microbeads. We prepared a collagen, activated photo-crosslinkable hyaluronan (API I), aminosilane and aminophosphate mixture, and then formed hydrogel microbeads by using axisymmetric flow focusing devices (AFFD) [1]. Phosphate or silane-modified surface would easily bind with inorganic molecules, and thus hydroxyapatite (IIA) was easily crystallized. Rat newborn primary osteoblasts (RNOs) were cultured onto microbeads and successfully calcified within 3 days. Bone remodeling takes long term (> 28 days) because it is difficult to enlarge the number of cells adhering to scaffolds with keeping its mechanical strength. Remodeling speed would be accelerated by accumulating calcified osteo-beads because of their rapid growing speed of IIA. Therefore, we believe that this method would be useful for rapid preparation of bone grafts.