Alginate/poly (lactic-co-glycolic acid)/calcium phosphate cement scaffold with oriented pore structure for bone tissue engineering

In this Study, the alginate/calcium phosphate cement (CPC) scaffolds with oriented pore structure were fabricated by unidirectional freeze casting and poly (lactic-co-glycolic acid) (PLGA) was used to infiltrate into the macropores to strengthen the scaffolds. By modifying the liquid to powder ratio, the porosity and pore size of the alginate/CPC scaffold could be controlled. At the liquid to powder (LIP) ratio of 3.25, scaffolds possessing open directional macropores and a total porosity of 89.24%, could be achieved. The size of the tubule-like macropores Could reach 100-200 mu m in their radial dimension and more than 1000 pm in the axial one, with macropores well-regulated arrayed. Increasing the LIP ratio would significantly decrease the mechanical strength of alginate/CPC scaffolds. The compressive strength and toughness of scaffolds Could be greatly improved via PLGA reinforcement. Three mechanisms of PLGA reinforcement ran as follows: participating in the external load, strengthening the matrix, and patching the defects of CPC pores wall. Alginate/PLGA/CPC scaffold preserved the open directional macropores and might be a potential scaffold for bone tissue engineering. (c) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 89A: 980-987, 2009