Abstract
Collagen/calcium phosphate composite materials were prepared using an alkaline phosphatase-catalyzed hydrolysis of water-soluble phosphate esters in the presence of calcium ions. We prepared a collagen/calcium phosphate composite film by adding sequentially calcium chloride, disodium glycerophosphate and alkaline phosphatase to collagen solution and subsequent drying of the resultant composite suspension in a template. The calcium phosphate contained in the film was determined to be mainly hydroxyapatite from FT-IR and X-ray diffraction analysis. The film little swelled in water to keep its original morphology, while a collagen film became solubilized. This suggests the binding between collagen and calcium phosphate in complex materials. When the preosteoblast cell line, MC3T3-E1 cells were cultured on the film, the film was found to support the osteoblastic differentiation from the measurement of alkaline phosphatase activity, which is an early differentiation marker.
