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171.
用丝素蛋白(SF)对微生物合成的高分子聚合物聚(3-羟基丁酸酯-co-3-羟基己酸酯)(PHBHHx)进行亲水改性,以提高材料的生物相容性.水接触角测定和表面自由能分析表明,丝素蛋白在支架表面吸附,使PHBHHx材料表面的水接触角从90°降至51°,表面自由能从37.9 mJ/m2增至57.4 mJ/m2,因而增加了材料的亲水性.进一步对亲水性改性前后PHBHHx多孔支架与人脐静脉内皮细胞(HUVECs)的相容性进行了比较.MTT法细胞活力分析表明,细胞在支架上培养3,5,7天后,其在SF改性PHBHHx多孔支架上的活力显著高于在未改性的PHBHHx支架上的活力;扫描电镜观察细胞生长形貌表明,细胞在改性后多孔支架上黏附及生长5天后,形成了连续细胞单层,其生长状态优于在未改性的PHBHHx支架上的生长状态;胶原含量测定表明细胞在改性后支架上比在未改性支架上有更好的胶原分泌能力,即改性后支架更利于诱导HUVECs分泌细胞外基质(ECM)从而构建类似体内的生长环境. 相似文献
172.
DSC, attenuated total reflexion infrared (ATR-FTIR), and Raman microspectroscopy were used for the first time in a close to in vivo environment to study ready-to-spin Bombyx mori silkworms. The aim was to understand the change of the fibroin backbone organisation from the gland to the fibre. Raman shifts of the Amide I components reveal a strong change of organisation in the middle part of the hydrated gland, as anticipated previously measured modifications of salts concentrations and pH. Series of bands characteristics of the fully hydrated silk disappear, as observed for spider silk, despite the different aminoacid sequence. Confirmation is obtained from IR spectra taking into account the superimposed water component. The change of the silk–water interaction in the central part of the gland, from a hydrophobic to hydrophilic behaviour, is related to the water content decrease along the gland. pH sensitive carboxylate side chains markers confirm the modification. Fibroin organisation was also studied in the dried gland and in the spun fibre. The fibre extrusion by orients the fibroin chains along the fibre axis, with intercalated water molecules, leading to a material with specific mechanical properties, compared to the amorphous dried gland. 相似文献
173.
《Analytical letters》2012,45(10):1286-1296
To investigate environmental effect on cultural materials, Fourier transform infrared technique (FTIR/ATR) was applied to analyze the silk aging process. Changes in chemical and conformational structures of silk fabric undergoing ultraviolet induced degradation were investigated. The IR spectra provided strong bands of photosensitive amide I, II, and III. For overlapping amide III region, both of the original and second-derivative IR spectra revealed that UV irradiation induced the structural transformation from β-sheet domain to β-turn conformation, which was supported by the increase of β-turn marker band at 1015 cm?1 associated with polyglycine. Additionally the reduced bands associated with (GlyAla)n segment at 1000 and 976 cm?1, and the decreased band at 1070 cm?1 related to β-sheet structure also illustrated the conformational transition. Furthermore, we applied a chemometric method of principal component analysis for the evaluation of silk degradation based on variations in amide I spectral region. The score plot using the first two principal components effectively summarized the general trend of silk-aging and revealed the quick degradation appeared in the initial stages (12 h and 24 h) and the 108-hr stage. This work provides a potential novel application of the infrared spectroscopy in noninvasive qualitative and quantitative investigation of silk degradation. 相似文献
174.
2,2,3,3,4,4,5,5-Octafluoropentyl acrylate was grafted onto silk fiber in a two-step heterogeneous system through the vinyl bonds of acryloyloxyethyl isocyanate modified on the silk.The grafted copolylner was analyzed by FTIR and WAXD,and the results revealed that the fluoroacrylate was successfully grafted onto silk fiber and the crystalline structure of silk fibroin withβ-sheet structure was not changed after graft copolymerization.The FT-IR corrected method was used to simulate the grafting yield onto ... 相似文献
175.
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177.
采用不同油相制备了系列丝素蛋白乳液, 研究了丝素蛋白浓度、 油相体积分数和油相极性对丝素蛋白的乳化活性指数、 丝素蛋白乳液的稳定性和类型及乳液液滴的微观形态、 粒径与zeta电位的影响, 探讨了丝素蛋白的乳化活性和乳液稳定机制. 结果表明, 丝素蛋白具有两亲性和表面活性, 可在油水界面富集并形成稳定的黏弹性保护膜; 丝素蛋白的乳化活性随其浓度的增大而减小, 随油相体积分数的增大而增大; 丝素蛋白浓度和油相体积分数的增加可提高稳定乳液体积分数. 相似文献
178.
《Arabian Journal of Chemistry》2020,13(5):5526-5538
Bone tissue engineering has become one of the most effective methods for treating bone defects. In this study, an electrospun tissue engineering membrane containing magnesium was successfully fabricated by incorporating magnesium oxide (MgO) nanoparticles into silk fibroin and polycaprolactone (SF/PCL)-blend scaffolds. The release kinetics of Mg2+ and the effects of magnesium on scaffold morphology, and cellular behavior were investigated. The obtained Mg-functionalized nanofibrous scaffolds displayed controlled release of Mg2+, satisfactory biocompatibility and osteogenic capability. The in vivo implantation of magnesium-containing electrospun nanofibrous membrane in a rat calvarial defect resulted in the significant enhancement of bone regeneration twelve weeks post-surgery. This work represents a valuable strategy for fabricating functional magnesium-containing electrospun scaffolds that show potential in craniofacial and orthopedic applications. 相似文献
179.
A simple and facile synthetic methodology for fabricating the regenerated silk fibroin(RSF)-based hydrogel which consisted of the in situ generated magnetic ferriferous oxide(Fe_3O_4) was developed. Using the co-precipitation of Fe~(2+) and Fe~(3+) within the RSF-based hydrogel with 90% RSF and 10% HPMC(hydroxypropyl methyl cellulose), the as-prepared RSF/Fe_3O_4 hydrogel not only showed high strength of saturation magnetization, but also exhibited excellent catalytic activities. For example, with the assistant of 3,3′,5,5′-tetramethylbenzidine(TMB), the RSF/Fe_3O_4 hydrogel could detect H_2O_2 at a concentration as low as 1 × 10~(-6) mol·L~(-1). In addition, the catalytic activities were able to be maintained for a long term under various conditions. These findings suggest that the RSF-based materials can be endowed with interesting properties, and have great potential for the applications in the fields of biotechnology and environmental chemistry. 相似文献
180.
随着环境污染、资源枯竭和医疗健康等问题的加剧,研发同时满足特定使用性能、安全性及可再生性的新型材料成为当前的发展趋势.而丝素蛋白材料正是以天然蚕丝为基本原材料,经一定的加工和功能化而形成的具有特殊结构、独特性能和广泛应用的生物质材料,近年来在生物医药、生物电子、智能传感等领域展现出巨大的应用潜力.本专论总结了丝素蛋白纤维及功能化材料的最新成果,结合本课题组相关工作,重点阐述了再生丝素蛋白纤维的仿生制备、生物医用支架的构筑与功能化、智能电子材料的设计以及天然多功能蚕丝及其构筑基元制备的研究进展,以期为高性能丝素蛋白材料的设计与构筑提供指导和借鉴. 相似文献