Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou Key Laboratory of Biomedicine and Advanced Dosage Forms, School of Life Sciences, Taizhou University, Zhejiang, Taizhou 318000, China; Hubei Provincial Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hubei Engineering University, Xiaogan 432000, China.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
Int J Biol Macromol. 2023 Dec 31;253(Pt 1):126596. doi: 10.1016/j.ijbiomac.2023.126596. Epub 2023 Aug 28.
Sodium alginate (SA)-based implantable scaffolds with slow-release drugs have become increasingly important in the fields of biomedical and tissue engineering. However, high-molecular-weight SA is difficult to remove from the body due to the lack of SA-degrading enzymes. The very slow degradation properties of SA-based scaffolds limit their applications. Herein, we designed a series of biodegradable oxidized SA (OSA)-based scaffolds through amide bonds, imine bonds and hydrogen bridges between OSA and silk fibroin (SF). SF/OSA-0.4 with a blend ratio of 4/1 was chosen for further polydopamine (PDA) surface modification studies through the optimization of those parameters such as different OSA oxidation degrees, and blend ratios. PDA modified SF/OSA-0.4 (Dopa/SF/OSA-0.4) showed the excellent stability, better stretchable properties, a uniform interconnective porous structure, high thermal stability, a low hemolysis ratio and cytotoxicity. In vitro degradation experiments showed that the degradation rate of SF/OSA was significantly higher than that of SF/SA, but the degradation slowed again after PDA modification. Interestingly, the degradation of Dopa/SF/OSA-0.4 in vivo was significantly faster than that in vitro. Dopa/SF/OSA-0.4 was also more conducive to new tissue growth and collagen bundle formation. Moreover, Dopa/SF/OSA-0.4 improved the absorbability of RhB (model drug) and reduced the sudden release of RhB during the sustained release.
基于海藻酸钠（SA）的植入式载药支架在生物医学和组织工程领域变得越来越重要。然而，由于缺乏 SA 降解酶，高分子量的 SA 很难从体内去除。基于 SA 的支架非常缓慢的降解特性限制了它们的应用。在此，我们通过酰胺键、肟键和氧化 SA（OSA）与丝素蛋白（SF）之间的氢键设计了一系列可生物降解的氧化 SA（OSA）基支架。通过优化不同的 OSA 氧化程度和混合比例等参数，选择 SF/OSA-0.4（混合比为 4/1）进行进一步的聚多巴胺（PDA）表面改性研究。PDA 修饰的 SF/OSA-0.4（Dopa/SF/OSA-0.4）表现出优异的稳定性、更好的拉伸性能、均匀的互联多孔结构、高的热稳定性、低的溶血率和细胞毒性。体外降解实验表明，SF/OSA 的降解速度明显高于 SF/SA，但 PDA 修饰后降解速度再次变慢。有趣的是，Dopa/SF/OSA-0.4 在体内的降解速度明显快于体外。Dopa/SF/OSA-0.4 也更有利于新组织的生长和胶原束的形成。此外，Dopa/SF/OSA-0.4 提高了 RhB（模型药物）的吸收能力，并减少了 RhB 在持续释放过程中的突释。
