Fabrication of Porous alpha-TCP/Gellan Gum Scaffold for Bone Tissue Engineering

摘要

alpha-tricalcium phosphate (alpha-TCP, alpha-Ca-3(PO4)(2)) receives great attention for bone repairing due to its biodegradability and capability of transformation to human bone's main inorganic components, hydroxyapatite (HAp). alpha-TCP porous scaffold is easily procurable by sintering of the low-temperature polymorph of TCP, alpha-TCP. Still, porous body of alpha-TCP is too brittle to being handled and shaped, limiting its clinical application as implant materials. To improve mechanical properties of alpha-TCP porous scaffold, the present study focused on coating of a type of polysaccharides on alpha-TCP scaffolds. Gellan gum was chosen as the polysaccharide for coating because of its biodegradability as well as the potential acting as substrate for HAp deposition during hydration of alpha-TCP after exposure to body fluid. After coating of gellan gum on alpha-TCP scaffolds with porosity of 75 vol%, the compressive strength increased from 0.45 MPa to around 2.00 MPa. Among the coated scaffold, the maximum compressive strength, 3.97 MPa, was obtained on the scaffold with porosity of 63 vol%. Improvement of mechanical properties of alpha-TCP/gellan gum composites was achieved to show easy handling performance for a bone substitute for tissue repairing. The dissolving rate of the coated scaffolds was also controlled by adjusting the concentration of GG solutions.