The Outlook of the Development of Innovative Products from Biocompatible Natural Spider Silk in the Beauty Thread-Lifting Industry

Embedding thread lift rhytidectomy,also known as“thread lifting”in China,with the natures of simple operation,less trauma and quick recovery,is progressively used in clinical practice as a new technology of face lifting.Herewith,a brief introduction of the previous advances of thread lifting techniques and materials in the facial beauty industry,combined with the discussion on various types of sutures,common complications,and the site of actions were provided.The main limitations of present thread lifting material include:(1)the use of non-absorbable sutures is liable to cause allergies and a series of complications;(2)the absorbable sutures are easily degradation,and people need to reshape in a relatively short period.Therefore,the high biocompatible spider silk was proposed as a novel material of thread lifting suture and related devices,the advantages and preliminary achievements on spider silk were also addressed.

Molecular Fundaments of Mechanical Properties of Spider Silk

Dragline,framework and cocoon silk fibers of Araneus Ventricosus were used for this study.To investigate the microstructure mechanisms of stress-strain behavior of spider silk,firstly,amino acid compositions were analyzed and molecular conformations and crystallinity were measured with Raman spectra and X-ray diffraction respectively.The results showed that there were more amino acids with large side groups and polar ones in spider silk than those of Bombyx silk,and the amino acid distribution varied with different spider silk.The molecular structures were mainly α-helix and β-sheet,and random coil and β-turn existed as well.The proportions and arrangement of these conformations of dragline silk were different from framework and cocoon silk fibers.Microstructure was one of important factors of excellent mechanical properties of spider silk.Crystallinity of spider silk was very low,which implied that the roles of crystal on spider silk were not as great as other protein fibers.

Recombinant Pyriform Spider Silk Expression and Wet-Spinning

Spider silk is capturing the attention of scientists for its mechanical properties,biocompatibility,and biodegradability.Spiders can produce six types of silks,as well as special glue,which are used for survival and reproduction.During the last years of research,scientists deciphered gene sequences and expressed the most common types of spider silks.However,matching the mechanical properties of recombinant spider silks to native ones is still a big challenge.Moreover,in-depth studies are mostly focused on natural and recombinant ampullate silks,and only a few studies showed achievements on pyriform spidroin(PySp).In this study,repeatable parts of PySp were expressed,purified,and spun into fibers.Recombinase cloning strategy allowed to create highly-repetitive region parts clones efficiently in comparison to the traditional restriction enzyme cloning technique.A cost-effective high-yield purification strategy was used.This study provides strategies that can help to design recombinant spider silks with the same mechanical properties as native spider silks.

Conformational Transitions and Self-assembly of Regenerated Spider Silk Protein in Water

Spider silk, relying on its exceptional mechanical properties, has attracted extensive attention throughout the world. The structure of a material can influence its mechanical properties. Investigation of the structure of spider silk includes amino acid composition, molecular structure, self-assembly, and crystallization, among other characteristics. Herein, the effects of concentration, time, alkali metal ions （Na^＋and K ^＋ ） and pH on the conformational transition and self-assembly of regenerated Ornithoctonus huwena spider dragline silk protein （spidroin） in water were investigated using circular dichroism （CD） and atomic force microScopy （AFM）. Spidroin concentration, time and Na ＋ ions slightly influenced the conformational transition of spidroin molecules. However, K ＋ ions and pH induced the formation of a β- sheet structure. Increasing spidroin concentration or time increased the aggregation of spidroin and enhanced the formation of nanoffiaments. K ~ ions enhanced the serf-assembly of spidroin into nanofilaments. The self-assembled nanofilaments appeared at a pH of approximately 6. 11. Both lower and higher pH induced aggregation. At a lower pH, the aggregation was composed of nanopartides, whereas higher pH induced the aggregation of nanoffiaments, likely from the synergistic effect of Na ^＋ ions and pH.

Study of Spider Silk Fibers by Raman Microscopy

Spider silk fibers of species of the genera Araneus, Gasteracantha, and Linothele sericata were studied. The fibers are composed of axial threads and lateral villi, allowing adhesion to surfaces. Raman spectroscopy was used to determine the surface and internal composition of the threads forming the structure. In the three species, the characteristic amino acid peaks of the spider web were found between 2871 and 2975 cm-1, which belong to L-glycine, L-alanine, L-glutamine, and L-proline. The threads are composed of a protective layer mainly composed of amides, alanine, and glycine. The fibrils surrounding the axial fibers consist mainly of amide II (1533 cm-1), which allows adhesion between the thread and the surfaces onto which the spider weaves the web. For the genus Linothele sericata, there is a peak on the surface of this spider web located at 2145 cm-1, which is associated with isonitriles with R-N-C bonds.

Innovations in spider silk-inspired artificial gel fibers:Methods,properties,strengthening,functionality,and challenges

Spider silk,possessing exceptional combination properties,is classified as a biogel fiber.Thereby,it serves as a valuable origin of inspiration for the advancement of various artificial gel fiber materials with distinct functionalities.Gel fibers exhibit promising potential for utilization in diverse fields,including smart textiles,artificial muscle,tissue engineering,and strain sensing.However,there are still numerous challenges in improving the performance and functionalizing applications of spider silk-inspired artificial gel fibers.Thus,to gain a penetrating insight into bioinspired artificial gel fibers,this review provided a comprehensive overview encompassing three key aspects:the fundamental design concepts and implementing strategies of gel fibers,the properties and strengthening strategies of gel fibers,and the functionalities and application prospects of gel fibers.In particular,multiple strengthening and toughening mechanisms were introduced at micro,nano,and molecular-level structures of gel fibers.Additionally,the existing challenges of gel fibers are summarized.This review aims to offer significant guidance for the development and application of artificial gel fibers and inspire further research in the field of high-performance gel fibers.

Determination of energy dissipation of a spider silk structure under impulsive loading

Various researches and studies have demonstrated that spider silk is much stronger and more deformable than a steel string of the same diameter from a mechanical approach. These excellent properties have caused many scientific disciplines to get involved, such as bio-mechanics, bio-materials and bio-mimetics, in order to create a material of similar properties and characteristics. It should be noted that the researches and studies have been oriented mainly as a quasi-static model. For this research, the analysis has taken a dynamic approach and determined the dissipation energy of a structure which is made of spider silk ＂Dragline＂ and produced by the Argiope- Argentata spider, through an analytical-experimental way, when being subjected to impulsive loading. Both experi- mental and analytical results, the latter obtained by using adjusted models, have given high levels of dissipation energy during the first cycle of vibration, which are consistent with the values suggested by other authors.

Morphology and Microstructure of Spider Dragline Silk from Araneus Ventricosus

The spider dragline silk has excellent mechanical properties. The stress- strain curves of dragline silk fibers have intraspecific and intraindividual variability because of the spider’s active control during spinning process. To investigate the relationship between the morphology of dragline silk fibers and spinning conditions, four samples were made at the reeling rates of 1 mm/s, 20 mm/s, 43.5 mm/s and 110 mm/s from the major ampullate glands of Araneus Ventricosus and the other two of dragline silks were prepared from a crawling or dropping spider. The surface microstructure and nanofibril characteristic were analyzed with atomic force microscopy (AFM). AFM images of 2 000 nm *2 000 nm and 500 nm*500 nm of these samples showed that the spinning condition influenced the surface roughness and fibril size, while AFM images of 200 nm*200 nm clearly displayed that dragline silk of Araneus Ventricosus included sheet macro-conformation structure. These results can facilitate the further investigation of the spinning mechanism of a spider in order to understand mechanical properties and macromolecular structures of dragline silk.

基于科研历程的“生物反应器的制备”高三复习课教学设计

以“构建高效生产蛛丝蛋白的生物反应器”这一真实科研情境为背景,以科研历程为主线,以任务驱动学生合作探究,从个体、细胞水平构建制备生物反应器的多样化方案,从分子水平比较同一反应器的不同制备方案,培养学生的工程学思维,发展学科核心素养。

蜘蛛丝蛋白纤维的研究进展

蜘蛛丝是一种具有卓越力学性能和生物相容性的天然材料,近年来在医学、纺织、航空、军事等领域得到了广泛的应用。本文首先介绍了蜘蛛丝蛋白的基本结构与性质,然后梳理了目前合成蜘蛛丝纤维的主要方法,包括遗传工程、溶剂纺丝和湿法纺丝等。在此基础上,分析了现有研究中存在的问题及挑战,并展望了未来研究方向。

蛛丝蛋白载药膜的结构表征及其降解性能研究

为治疗化疗后的口腔黏膜炎,以敬钊缨毛蛛的天然蛛丝作为成膜材料制备载药膜剂,并对膜剂特性进行表征。采用溶剂浇铸法制备出蛛丝蛋白膜,通过水接触角实验、傅立叶红外光谱法、X-射线衍射法、扫描电镜评价膜剂的结构特征,探讨了膜剂的降解性。本试验所制备膜剂表征实验证明药物成功载入膜中,降解实验表明膜剂在人工唾液中7 d内的降解失重率仅5%,在人工胃液中72 h降解失重率达到65%以上。以天然蛛丝-六氟异丙醇溶液为成膜液,采用溶剂浇铸法可成功制备出载有肌苷药物的口腔膜剂。

Surface Characterization of As-Spun and Supercontracted <i>Nephila clavipes</i>Dragline Silk

Dragline spider silks have relatively high mass-based mechanical properties (tensile strength, elongation to break and rupture energy) and are environmentally responsive (supercontraction). In order to produce new synthetic fibers with these properties, many research groups have focused on identifying the chemical composition of these fibers and the structure of the fiber core. Since each fiber also has an outer skin, our study will provide a detailed understanding of the silk surface morphology, the response of the surface morphology to environmental conditions and processing variables, and also determine if the silk surface has a definitive patterning of charged amino acids. Specifically, by using force microscopy and functionalized nanoparticles, the present study examines 1) how the silk surface (topography, average roughness) is altered due to prior mechanical loading (viz. reeling speed), 2) alterations in morphology due to environmental conditions (supercontraction, storage time), and 3) the negatively and positively charged regions along with the surface using both force and nanoparticle mapping. Roughness data taken on dragline silk collected from Nephila clavipes spiders revealed that the surface comprised both smooth (5 nm RMS) and rough (65 nm RMS) regions. Supercontracted silk (from immersion in0.01 MPBS during AFM testing) showed higher surface roughness values compared to spider silk tested in the air, indicating that the surface might be reorganized during supercontraction. No correlation was found between surface roughness and neither collection speed nor aging time for the as-spun or supercontracted fiber, demonstrating the surface stability of the dragline silk over time in terms of roughness. Both the force microscopy and the nanoparticle methods suggested that the density of negatively charged amino acids (glutamic acid, aspartic acid) was higher than that of the positively charged amino acids (lysine, asparagine, and histidine).

形变导致的蜘蛛大壶状腺丝力学行为的记忆与变异

纤维材料的形变与力学行为之间的关系密切。在自然条件下蛛丝会被反复拉伸,但其被拉伸后的力学行为被搁置的时间与形变效应鲜见报道。为此,本工作采用METS电子万能试验机测试研究了反复定伸长拉伸松弛后的间隔时间与形变对蜘蛛大壶状腺丝的力学行为的影响。结果表明,不论天然的还是经水最大限度超收缩干燥后的大壶状腺丝被定伸长反复拉伸过屈服点和屈服区甚至拉至加强区的力学行为曲线都能很好地重叠;经长时间(≥20 min)间隔后也只需一次拉伸就能不受拉伸历史的影响重现之前的力学行为,具有良好的纵向拉伸的形状与力学行为记忆。通过增加应变值对蜘蛛大壶状腺丝进行一系列的加载-卸载循环试验,并分析这些循环中其应力-应变曲线,计算每个循环中它的弹性模量、屈服应力、吸收和耗散的能量,以评估这些力学性能参数随循环增加的微观进化与演变。研究表明,蜘蛛丝力学行为的记忆与变异可以通过不可逆和可逆两种变形微观机制及其组合来解释,其中材料的粘弹性起主导作用。这些研究对人们进行新型功能纤维材料的仿生设计具有重要的指导意义。

重组人胰岛淀粉样多肽的制备及评价

人胰岛淀粉样多肽(hIAPP)的淀粉样变与2型糖尿病(T2D)的发生发展密切相关。为解决体外评价化合物抗hIAPP淀粉样变活性所需hIAPP存在化学合成困难、成本高、溶解性低和批次稳定性差等问题,本研究以蛛丝蛋白N端结构域突变体NT作为融合标签,构建大肠杆菌高效表达hIAPP体系。通过优化表达条件和分离纯化工艺,获得重组hIAPP(rhIAPP),并对rhIAPP二硫键形成、淀粉样变能力和淀粉样变产物的毒性进行检测。融合蛋白质以包涵体形式存在,经过尿素变性和亲和层析纯化得到融合蛋白质产量为70 mg/L发酵液,融合蛋白质经过复性、凝血酶切除融合标签和进一步纯化,最终得到rhIAPP产量为6 mg/L发酵液。检测显示,rhIAPP的巯基未形成二硫键。rhIAPP具有“S”型淀粉样变曲线,其形成的β-折叠结构远多于化学合成的hIAPP(chIAPP),化合物姜黄素能显著抑制2种来源hIAPP的淀粉样变。细胞毒检测表明,rhIAPP在与红细胞孵育过程中促进红细胞溶血。

两种蜘蛛丝的拉曼光谱及力学性能的研究

蜘蛛丝是一种蛋白质纤维,有较高强度及韧性,其因良好的综合力学性能成为重点关注的天然材料之一,但研究对象多为园蛛科络新妇属,其他科属的蜘蛛丝鲜有科研者涉及。为扩展蜘蛛丝的研究范围,利用云南丰富的蜘蛛资源,早期工作便对各科属蜘蛛丝的光谱学性能进行探讨,该实验选用隶属于褛网蛛科的泰褛网蛛、园蛛科的黔美园蛛作为对象,对其骨架丝进行研究。通过获得两种丝的偏振拉曼光谱,从而分析其蛋白质结构与力学性能的关系,为后期合成高性能材料提供相应研究依据。

载美洲大蠊提取物蛛丝蛋白膜的制备、表征及体外释药性和细胞毒性考察

目的制备一种载美洲大蠊提取物的蛛丝蛋白膜,并对其进行表征及体外释药性和细胞毒性考察。方法以天然敬钊缨毛蛛蛛丝为原料,美洲大蠊提取物为模型药物,采用溶剂浇铸法制备载药蛛丝蛋白膜(后文称“载药膜”),同法制备不含美洲大蠊提取物的载药材料基质蛛丝蛋白膜(后文称“空白膜”)。经静态水接触角、傅里叶红外色谱、X-射线衍射以及扫描电镜等技术对膜剂进行表征,从不同角度分析膜剂结构;通过体外模拟药物在人工唾液中的释放特性评价药物的缓释性能;以MTT法验证载药膜的体外细胞毒性。结果制备得到的载药膜的静态水接触角均小于90°,且小于空白膜;载药膜在1500~1700 cm^(-1)存在美洲大蠊提取物多肽的特征吸收峰;同时X-射线衍射和扫描电镜也证实美洲大蠊提取物已成功负载到膜剂中。该膜剂可在人工唾液中释药时长逾200 min。MTT实验结果显示,空白膜和载药膜作用后的细胞增殖率分别为84.6%、79.4%(均大于70%),无显著的潜在细胞毒性。结论以天然蛛丝所制备的载药膜在人工唾液中具有一定的缓释效果,有望作为一种具优异生物相容性的药物缓释载体应用于临床。

两种蜘蛛蛛网框丝的蛋白质结构及力学性能研究

蜘蛛丝作为一种天然的蛋白质纤维,有较高强度及韧性,其因良好的综合力学性能与特性而备受关注。依托云南省丰富的蜘蛛资源,将褛网蛛科泰褛网蛛(Psechrus ghecuanus)、园蛛科黔美园蛛(Araneus gratiolus)作为对象,以纺自大壶状腺的蛛网框丝作为研究材料,采用单纤维强力机、拉曼光谱仪与X射线衍射仪对两种蜘蛛的蛛网框丝进行测试研究。结果显示,两种丝有相似的拉曼图谱,β-折叠均平行于丝的轴向。但两种丝由峰强比反映出的各结构含量却有一定差别,其中泰褛网蛛丝中络氨酸的氢键更强,β-折叠结构的含量更高,因而具有更高的强度;黔美园蛛丝中β-折叠的取向水平更低,因而具有更高的韧性。此外,X射线衍射图谱测得泰褛网蛛丝及黔美园蛛丝的结晶度分别为33%及20%。

两种蜘蛛大壶状腺丝的拉曼光谱与力学性能研究

偏振拉曼光谱能有效分析蜘蛛丝的蛋白质结构特征,早期的研究对象多为人工抽取的络新妇属蜘蛛的曳丝,而同为大壶状腺丝的骨架丝及其他科属的蛛丝却很少被研究报道。为探讨自然状态下蛛丝蛋白二级结构与力学性能之间的关系,使用偏振拉曼光谱对艾蛛属的黑腹艾蛛、希蛛属的翘腹希蛛的骨架丝进行研究。结果表明,这两种丝有着相似的氨基酸序列和结构,且β-折叠平行于丝的轴线,但翘腹希蛛丝其余大部分的二级结构却垂直于丝的轴线,这一特殊结构也导致翘腹希蛛丝的断裂伸长率(42.18±11.84%)高于黑腹艾蛛丝(23.85±5.18%)。同时,从不同峰强比、方向不敏感光谱得出,翘腹希蛛丝β-折叠结构的取向度比黑腹艾蛛丝的高,但相近的β-折叠结构、络氨酸氢键含量导致两丝的断裂强度变化差异不显著。蛛丝拉曼光谱的重现性较好,可用于研究更多种类的蛛丝,为开发利用蛛丝提供依据。

桑蚕丝腺体和丝纤维中金属离子的含量

用不同的测试方法,即质子诱导X射线发射(PIXE)、电感耦合等离子体质谱(ICP-MS)和原子吸收光谱(AAS)对桑蚕丝腺体和丝纤维中金属元素的含量进行了详细的表征.结果表明,在桑蚕丝腺体和丝纤维中含有钠、镁、钾、钙、铜、锌、铁、锰八种金属元素,同时还可能含有微量的铷和锶.这些金属元素在丝腺体和各种丝纤维(蚕茧丝、强拉丝和脱胶丝)中的含量都有所变化,而这些变化可能与之在成丝过程(丝蛋白的构象转变过程)中所起的作用有关.

RGD-蜘蛛拖丝蛋白聚合物的生物合成与纯化

蜘蛛拖丝是自然界性能最好的蛋白质纤维之一 ,其独特的机械性能 ,良好的生物相容性和缓慢的可降解性 ,作为生物材料在组织工程领域有着潜在的应用前景。本文根据蜘蛛拖丝蛋白序列高度重复的特点 ,引入与细胞黏附有关的精氨酸 甘氨酸 天冬氨酸 (RGD)三肽 ,化学合成RGD 蜘蛛拖丝蛋白基因单体 ,通过头尾相连倍加构建策略 ,首次得到RGD 蜘蛛拖丝蛋白基因 8聚体和 16聚体。分别将这两种多聚体与原核高效表达载体 pET 30a(+)连接 ,转化大肠杆菌BL2 1(DE3) pLysS ,用IPTG诱导表达。SDS PAGE图谱显示表达产物分子量分别为 35KD和 6 0KD ,与理论值基本相吻合 ;蛋白质印迹分析这两种表达产物均显示特异性。文中对表达产物的纯化方法进行了初步的摸索。