Sichuan University, College of Polymer Science and Engineering, Chengdu, Sichuan province, 610065, PR China; Chengdu University of TCM, College of Acupuncture and Massage College,No. 37, Twelve Bridge Road, Chengdu,Sichuan province,610075，PR China.
Sichuan University, College of Polymer Science and Engineering, Chengdu, Sichuan province, 610065, PR China; Sichuan University,Laboratory animal center, No.24 South Section 1, Yihuan Road, Chengdu ,Sichuan province,610065, PR China.
Mater Sci Eng C Mater Biol Appl. 2020 Apr;109:110544. doi: 10.1016/j.msec.2019.110544. Epub 2019 Dec 12.
Traditional CPC cements have attracted wide attentions in repairing bone defects for injectability, easy plasticity and good osseointegration. However, its further application was limited by poor mechanical properties, long setting time and unsatisfactory biocompatibility. To solve these problems, polydopamine (DOPA) coated strontium-doped calcium polyphosphate (SCPP) fibers were added into CPC cements for the first time. A doping amount at fiber weight fraction of 0%, 1%, 2% and 5% was designed to develop a multifunctional composite fitting for bone tissues' regeneration and reconstruction and the optimum amount was selected through subsequent physicochemical and biological characterizations. The results implied DOPA coating successfully formed stable connections between SCPP fibers and CPC matrix, which simultaneously reinforced biomechanical strength and tenacity (5% SCPP/D/CPC samples exhibited more prominent mechanical property than others). In addition, 5% D/SCPP fibers doped composite cements were characterized as markedly-improved cytocompatibility: Sr introduction induced cytoactive and significantly accelerated proliferation, attachment and spreading of osteoblasts. Besides, it also stimulated the secretion of OT, Col-I and ALP from seeded MG63, which was a critical character for further inducing osteogenic process, mineralization and bone tissues formation. The promoted cytocompatibility and improved osteogenesis-related growth factors' secretion could be attributed to constant and controllable release of Sr and this deduction was approved by ICP analysis. In addition, Sr doping made this novel cement had a potential efficacy to inhibit aseptic loosening. In a word, present studies all demonstrated 5% SCPP/D/CPC composites could be a potential candidate material employed in bone regeneration and reconstruction for excellent mechanical property and cytocompatibility.
传统的 CPC 水泥因其可注射性、易塑性和良好的骨整合性而在修复骨缺损方面引起了广泛关注。然而，其进一步的应用受到机械性能差、凝固时间长和生物相容性不理想的限制。为了解决这些问题，首次将多巴胺（DOPA）涂层锶掺杂的钙聚磷酸盐（SCPP）纤维添加到 CPC 水泥中。设计了纤维重量分数为 0%、1%、2%和 5%的掺杂量，以开发一种多功能复合材料，适用于骨骼组织的再生和重建，并通过随后的物理化学和生物学特性选择最佳掺杂量。结果表明，DOPA 涂层成功地在 SCPP 纤维和 CPC 基质之间形成了稳定的连接，同时增强了生物力学强度和韧性（5%SCPP/D/CPC 样品表现出比其他样品更突出的机械性能）。此外，5% D/SCPP 纤维掺杂复合水泥表现出明显改善的细胞相容性：Sr 的引入诱导了细胞活性，并显著促进了成骨细胞的增殖、附着和扩散。此外，它还刺激了接种的 MG63 分泌 OT、Col-I 和 ALP，这是进一步诱导成骨过程、矿化和骨骼形成的关键特征。促进细胞相容性和改善成骨相关生长因子的分泌可归因于 Sr 的持续和可控释放，这一推论得到了 ICP 分析的证实。此外，Sr 掺杂使这种新型水泥具有抑制无菌松动的潜在功效。总之，目前的研究都表明，5% SCPP/D/CPC 复合材料可以作为一种潜在的候选材料，用于骨再生和重建，具有优异的机械性能和细胞相容性。
