Hubei Province Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hubei Engineering University, Xiaogan 432000, People's Republic of China.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People's Republic of China; Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, People's Republic of China.
Int J Biol Macromol. 2020 May 1;150:1314-1322. doi: 10.1016/j.ijbiomac.2019.10.141. Epub 2019 Nov 17.
In this study, silk fibroin (SF)/sodium alginate (SA) porous materials (PMs) with different blend ratios were generated using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) as crosslinking agent by a simple freeze-dried method. Degradation experiment of SF/SA PMs have been systematically investigated up to 18 days in Collagenase IA solution at 37 °C, Phosphate buffer saline (PBS) solution without enzyme was used as a control. The results showed SF/SA 50/50 PMs exhibited a lowest rate of weight loss, about 68% of the weight retained within 18 d in Collagenase IA solution. SEM images indicated Collagenase IA can degrade fibroin leading to collapse of the pure SF PMs, while SF/SA 50/50 PMs still possessed integrity of pore structure during enzyme degradation with increasing exposure time. The crystalline structure of the SF in the SF/SA PMs changed to silk II after degradation for 18 d. Furthermore, the results of the in vivo degradation by subcutaneous implantation in rats showed that all PMs can be degraded at different levels, and exhibited good subcutaneous histocompatibility to the host animals. The degradability was strongly correlated to the blend ratios in a series of SF/SA composite PMs, and insights gained in this study can serve as a guide to match desired degradation behavior with specific applications for the SF/SA composite PMs.
在这项研究中，采用 1-乙基-3-(3-二甲基氨基丙基)碳二亚胺（EDC）作为交联剂，通过简单的冻干法生成了不同混合比例的丝素蛋白（SF）/海藻酸钠（SA）多孔材料（PM）。在 37°C 的胶原酶 IA 溶液中，对 SF/SA PM 的降解实验进行了系统研究，长达 18 天；未加酶的磷酸盐缓冲盐水（PBS）溶液用作对照。结果表明，SF/SA 50/50 PM 的失重率最低，在胶原酶 IA 溶液中 18 天内保留了约 68%的重量。SEM 图像表明胶原酶 IA 可以降解丝素蛋白，导致纯 SF PM 坍塌，而 SF/SA 50/50 PM 在酶降解过程中随着暴露时间的增加仍然保持孔结构的完整性。SF/SA PM 中的 SF 的晶体结构在降解 18 天后转变为丝素 II。此外，通过皮下植入大鼠体内的降解结果表明，所有 PM 都可以在不同水平上降解，并对宿主动物表现出良好的皮下组织相容性。降解能力与一系列 SF/SA 复合 PM 中的混合比例密切相关，本研究的结果可以作为指导，将所需的降解行为与 SF/SA 复合 PM 的特定应用相匹配。
