抄録
The aim of this paper is to evaluate the effect of the coating with the adhesive protein on the mechanical properties of the HAp/collagen composite fibers, and then aimed to obtain the optimum design guideline of their preparation. We prepared the collagen fibers using the bio-inspired method, where the fibrosis and the cross-linking are generated at the same time. Here, 1-ethy-3carbodiimide hydrochloride (EDC) was selected as the cross-linking agent. Then, the adhesive protein was applied to the prepared collagen fibers. Here, the osteonectin was selected as the adhesive protein. Finally, the HAp crystals were deposited on the surface of the prepared collagen fibers using the biomimetic deposition method, where the collagen fibers are dipped into the pseudo body fluid alternately. The tensile tests were carried out using the micro-tensile testing device developed by the authors previously. As a result, the tensile strength of the HAp/collagen composite fibers tends to increase and then decrease with the increase of the EDC concentration, the osteonectin concentration and the HAp deposition time. The tensile strength of the HAp/collagen composite fibers prepared under the EDC concentration of 3-5 [mmol], the HAp deposition time of 50 [s] and the osteonectin concentration of 0.5 [μg/μL] was equivalent or even higher than that of the HAp/collagen composite fibers without osteonection prepared under their optimum condition. It can be considered that the osteonectin would act as the additional interfacial bonding factor between the collagen fibers and HAp crystals. Since the excessive interfacial bonding might embrittle the HAp/collagen composite fibers, the coating of the osteonectin should be carried out to the HAp/collagen composite fibers prepared under the moderately low EDC concentration and the moderately short HAp deposition time.
