Porous beta-tricalcium phosphate/collagen composites prepared in an alkaline condition

Bone substitute materials with natural bone-like structure are considered to be favorable for bone regeneration. In this work, porous beta-tricalcium phosphate (beta-TCP)/collagen composite consisting of bone-like microstructural units was prepared using nanosized beta-TCP particles and alkaline-disassembled collagen. The resulting composite showed a good interconnecting porous structure with approximately 90% porosity and 100 approximately 300 microm pore size. The pore walls were dense, and the combination status of collagen and nanosized beta-TCP particles demonstrated that nanosized beta-TCP particles tightly connected collagen microfibrils as a bone-like microstructural unit. MTT and alkaline phosphatase (ALP) assays showed that the porous composite had enhanced effects on cellular proliferation and activity of osteoblast compared with a control of pure collagen. It is suggested that the adoption of nanosized beta-TCP particles is a main contribution to the formation of the composite with a bone-like microstructural unit, and the unique microstructure could be a main role for the composite to have the positive influence on osteoblast cell proliferation.