Fabrication And Properties Of CF/PLA-PEG Composite Scaffold For Bone Tissue Engineering

A kind of modified carbon fiber/polylactic acid/polyethylene glycol (CF/PLA-PEG) composite scaffold for bone tissue engineering was prepared in this paper. The detail research was as follows:(1) The surface of carbon fiber was modified. PAN-based carbon fibers, as raw material, were treated by concentrated nitric acid and aminobenzoic acid, respectively. After treated by aminobenzoic acid, longitudinal grooves appeared on carbon fiber, but the tensile strength of carbon fibers did not appear significant changes. The mice fibroblasts (L929) were inoculated on three kinds of carbon fibers, the cell proliferation test showed that aminobenzoic acid treatments were more conducive to cell proliferation and differentiation. Infrared spectrum analysis showed that carbon fiber treated by aminobenzoic acid had more hydrophilic groups such as carboxyl and hydroxyl. The experiments proved that the carbon fibers treated by aminobenzoic acid were superior to other samples.(2) The effects of modified carbon fiber on mechanical properties of PLA-PEG scaffold were studied. The three-dimensional PLA-PEG bone tissue engineering scaffolds, with porosities of50±2%,60±2%and70±2%, were prepared by solution casting/particulate leaching method. With the increase of porosity, mechanical properties of the scaffold reduced, but the number of pores, the hydrophilicity and the degradation rate increased. Furthermore, three-dimensional CF/PLA-PEG scaffolds were prepared with mass fraction of0.5%and2%CF, respectively. It was found that the modified carbon fibers were randomly distributed in the scaffolds, and the mechanical properties and hydrophilicity of CF/PLA-PEG were improved.(3) Biological properties of modified CF/PLA-PEG scaffold were investigated. The mouse fibroblast cells (L929) and osteoblasts (MC3T3) were seeded in PLA-PEG scaffolds. The observations by using (SEM) and (LSM) showed that porosity is good for cell to adhere. It also indicated that increasing the porosity lead to lower mechanical properties, but much better biological properties of cells.The L929and MC3T3were seeded in CF/PLA-PEG scaffolds with different mass fraction. The cells could adhere successfully in the surface and the surrounding of carbon fibers. The addition of modified carbon fibers is helpful for cell proliferation according to the results of cell proliferation.Further, RGD was taken to modify2%CF/PLA-PEG scaffolds. It found much more cells on the surface of2%CF/PLA-PEG scaffolds. It indicated that RGD can be used to improve the biocompatibility of the scaffolds.Modified CF was used to strengthen PLA-PEG scaffolds. The resulting CF/PLA-PEG scaffolds possessed good mechanical properties, hydrophilicity and biocompatibility. CF/PLA-PEG scaffolds are expected to be applicated in bone tissue engineering.