Fabrication and evaluation of 3D printed poly(l-lactide) copolymer scaffolds for bone tissue engineering

The application of poly(L-lactic acid) (PLLA) in tissue engineering is limited due to its brittleness and uncontrollable degradation rate. In this study, the flexible p-dioxanone (PDO) and highly reactive glycolide (GA) units were introduced into PLLA segments by chemical modification to prepare poly(l-lactide-ran-p-dioxanone-ran-glycolide) (PLPG) copolymers. The copolymers were then processed into the PLPG scaffold by a 3D printing technology. The physicochemical properties of the PLPG copolymers were studied by NMR, DSC, XRD, GPC, and SEM. Furthermore, the mechanical properties, degradation properties, and biocompatibility of the PLPG scaffolds were also studied. The results showed that introducing PDO and GA units disrupted the regularity of PLLA, decreasing the crystallinity of the PLPG copolymers. However, introducing PDO and GA units could effectively improve the mechanical and degradation properties of the PLLA scaffolds. In vitro cell culture experiments indicated that the PLPG scaffolds supported proliferation, growth, and differentiation of MC3T3-E1 cells. The PLPG scaffolds reported herein, with controllable degradation rates and mechanical performance, may find applications in bone tissue engineering.