Novel polylactic acid porous scaffold reinforced with oriented magnesium wires for potential bone repair application

Abstract

Polylactic acid porous scaffold oriently reinforced by magnesium wires (PLA-Mg) for bone repair was proposed in this paper. Ca-P deposition layer formed on the surface of Mg wires in PLA-Mg after immersion, which illustrated that PLA-Mg had good ability of mineralization in vitro. In PLA-Mg, the corrosion of the Mg wire end was higher than that of the middle regions in Mg wire during immersion. Uniform and long-term release of Mg2+ in PLA-Mg followed exponential rules of decline, which could be predicted that the final concentration of magnesium ions (C(Mg2+)) of PLA-Mg during immersion could reach 42.14 ppm, which was among the range of normal physiological and pathological conditions. Besides, the effect of pH on the hydrolysis of PLA in PLA-Mg surpassed that of C(Mg2+), improving the crystallinity of PLA in immersed PLA-Mg with an increase of 39.6 % compared to that in the unsoaked PLA. Compressive strength of PLA-Mg could reach 2.07 ± 0.25 MPa, which was greatly improved in contrast to that of pure PLA. After immersion, the stability of Mg wires in immersed PLA-Mg was higher than that in the unsoaked one. These results could provide references for developing potential porous composite scaffolds towards bone repair.