Improved biocompatibility of novel poly(L-lactic acid)/ß-tricalcium phosphate scaffolds prepared by an organic solvent-free method

Xue-Feng Zhao^1,2, Xiao-Dong Li³, Yun-Qing Kang⁴, Quan Yuan^1,2
1State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, People's Republic of China; ²West China School of Stomatology, Sichuan University, Chengdu, People's Republic of China; ³Affiliated Hospital of Stomatology and College of Stomatology, Chongqing Medical University, Chongqing, People's Republic of China; ⁴College of Materials Science and Engineering, Sichuan University, Chengdu, People's Republic of China

Abstract: A porous poly(L-lactic acid)/ß-tricalcium phosphate (PLLA/ß-TCP) composite scaffold was fabricated using a novel technique comprising powder mixing, compression molding, low-temperature treatment, and particulate leaching without any organic solvent. The effect of this scaffold on osteoblast proliferation and differentiation was evaluated in vitro. The fabricated scaffold had a homogeneously interconnected porous structure with a porosity of 70% and compressive strength of 1.35 MPa. The methylthiazol tetrazolium values and alkaline phosphatase (ALP) activity of osteoblasts seeded on the solvent-free scaffold were significant higher than those of the control. Using real-time PCR, gene expressions of ALP, osteocalcin, and type 1 collagen were shown to be upregulated. As the method does not use any organic solvent, it eliminates problems associated with organic solvent residue and therefore improves the cell compatibility. It has a promising potential for the preparation of porous scaffold for bone tissue engineering.

Keywords: biocompatibility, biomaterials, composites, poly(L-lactic acid), ß-tricalcium phosphate