Para-amino benzoic acid doped micro-grooved carbon fibers to improve strength and biocompatibility of PLA-PEG

Para-amino benzoic acid (PABA), a folic acid related metabolite, was first introduced to fabricate micro-grooves and improve hydrophilicity over surfaces of carbon fibers (CFs). Then, engineered CFs/poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) biocomposites were fabricated by a solvent casting/particulate leaching method. We found that introducing small hydrophobic PABA molecules and fabricating patterned structures would lead to benign integrated interfaces between CFs and the PLA-PEG matrix. Specifically, the compressive strength of CFs/PLA-PEG was improved from 3.98 to 5.48 MPa. In addition, the CFs/PLA-PEG biocomposites significantly accelerated the adhesion and proliferation of pre-osteoblasts with minimized cytotoxicity. By comparing the cyto-compatibility of L929 and MC3T3 cells cultured on different modified PLA-PEG composites, it could be concluded that PABA-CFs not only overcame the limitation of poor strength of PLA-PEG, but also improved the cell growth. These results indicate that the PABA-CFs reinforced PLA-PEG biocomposites could be a potential alternative for tissue engineering scaffolds.