Hu Xulin, He Jian, Yong Xin, Lu Junlin, Xiao Jianping, Liao Yijun, Li Qing, Xiong Chengdong
Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu 610041, China.
Colloids Surf B Biointerfaces. 2020 Nov;195:111218. doi: 10.1016/j.colsurfb.2020.111218. Epub 2020 Jun 27.
Poly (lactic acid) (PLA), although extensively used as biomedical materials, has the distinct disadvantage of producing acidic byproducts which can lead to tissue inflammatory reactions and clinic failure. Here we presented a combination of Poly (lactic acid-co-trimethylene carbonate) and natural polymer chitosan, improving its compression resilience and reducing its acidic byproducts. In this case, we developed 3D scaffolds using solvent/nonsolvent technique sintered PLA-TMC and PLA-TMC/Chitosan microspheres with selected particle size (355-500 μm). By controlling the preparation methods and parameters, the porosity, pore size and mechanical properties of microsphere scaffolds can be designed and controlled. Strikingly, PLA-TMC/15 % Chitosan microsphere scaffolds possess shape-memory effect and rapidly recovered to initial shape when heated to 37℃ within 300 s. The microsphere scaffolds had a 3D porous architecture with pore size ranging from 105.67 ± 12.51 μm to 129.69 ± 11.39 μm. The mechanical and physicochemical properties of microspheres and scaffolds were characterized in details. Moreover, all microsphere scaffolds were qualified as their compressive modulus (120.36 MPa -195.32 MPa) matched the cancellous bone during 16 weeks degradation. Furthermore, CCK8 cell proliferation assay and ALP activity assay verified that the scaffolds were non-toxic and conductive to cell adhesion. The scaffolds are expected to be used in bone regeneration and bone repair field.
聚乳酸（PLA）虽然被广泛用作生物医学材料，但有产生酸性副产物的明显缺点，这可能导致组织炎症反应和临床失败。在此，我们展示了聚（乳酸 - 共 - 碳酸三亚甲基酯）与天然聚合物壳聚糖的组合，提高了其抗压弹性并减少了酸性副产物。在这种情况下，我们使用溶剂/非溶剂技术烧结了选定粒径（355 - 500μm）的PLA - TMC和PLA - TMC/壳聚糖微球来制备3D支架。通过控制制备方法和参数，可以设计和控制微球支架的孔隙率、孔径和机械性能。引人注目的是，PLA - TMC/15%壳聚糖微球支架具有形状记忆效应，在300秒内加热到37℃时能迅速恢复到初始形状。微球支架具有3D多孔结构，孔径范围为105.67±12.51μm至129.69±11.39μm。详细表征了微球和支架的力学和物理化学性质。此外，所有微球支架均符合要求，因为它们在16周降解过程中的压缩模量（120.36MPa - 195.32MPa）与松质骨相匹配。此外，CCK8细胞增殖试验和ALP活性试验证实了支架无毒且有利于细胞粘附。这些支架有望用于骨再生和骨修复领域。
