人造蜘蛛丝问世：强度超钢铁

可不是只有电影里的蜘蛛侠才能制造出那么强韧的“人造”蜘蛛丝哦。近日，美国科学家利用转基因蚕打造人造蜘蛛丝，强度甚至超过钢铁，这项研究突破将孕育出强度更高的织物纤维，可用于整容手术、制造包扎烧伤患者的绷带以及防弹背心。科学家们通过转基因蚕吐出的纤维表达蜘蛛基因序列，获得弹性和延展性更高的蜘蛛丝蛋白。作为一种生物材料，蜘蛛丝拥有巨大用途：     

成丝的速度与方式和蜘蛛丝力学性能的关系

为了分析蜘蛛丝的力学性能和成丝条件间的关系,研究了不同速度下人工卷取的蜘蛛牵引丝以及蜘蛛垂直下落时分泌的牵引丝的力学性能.研究结果表明,随着卷取速度的增大,蜘蛛丝的断裂强度有一极大值,在高速卷取时强度的变化较低速时平缓.垂直下落时蜘蛛分泌的牵引丝的综合力学性能优异,但断裂强度不一定大于人工卷取的丝.成丝速度和成丝方式都对蜘蛛丝的性能有很大影响.     

纤维之星——人造蜘蛛丝

小小的蜘蛛用体液抽出晶莹的长丝,编织一张张圆网,捕捉虫蛾为食物。人类从蜘蛛丝的突出优点中得到启示,正在努力实现人造蜘蛛丝的梦想。在这一领域中探寻的是美国康奈尔大学的应用生命研究所所长詹林斯教授。 天然蜘蛛丝的直径为习微米左右,其单位截面积的牵引强度相当于钢的5倍。蜘蛛丝还具有卓越的防水和伸缩功能。詹林斯教授认为,如果制造出一种具有天然蜘蛛丝特点的人造蜘蛛丝,那么这种丝就具有广泛     

美国研制"生物钢"

据英<新科学家>1998年10月10报道,美国得克萨斯州魁北克的研究人员发现,蜘蛛丝甚至具有比"开夫拉"纤维和高强度钢还要高的强度.     

新型人造蜘蛛丝超强韧

蜘蛛丝在自然界中很常见,然而它非常不普通,一直吸引着科学家研究和仿制。据实验研究,在高湿的环境中,蜘蛛丝可伸长5倍长度,并且伸长后几乎不反弹、不旋转。伸长的蜘蛛丝遇水会恢复到初始长度,这使它被来袭的猎物撞击而伸长后可以自动修复并继续使用。这一切都表明蜘蛛丝具有极佳的机械性能。     

让蜘蛛吐“钢丝

也许你不知道,同样粗的蜘蛛丝和钢丝相比,蜘蛛丝的强度竟是钢丝的100倍天然蜘蛛丝具有易被生物分解的毫微纤维构造,厚度虽仅为人类毛发的1/10,但当密蜂以超过30     

二十一世纪新型纤维--蜘蛛丝

介绍了蜘蛛丝的形成、结构性能,利用生物技术开发蜘蛛丝的几种途径及应用前景。     

蜘蛛丝的结构与机械性能研究进展

蜘蛛丝是一种天然动物蛋白纤维,含有(GPGXX)n/(GPGQQ)n、An/(GA)n、(GGX)n等多种重复多肽序列,具有多样的分子结构、机械性能与生物生态学功能,同时还具有强度高、弹性好、初始模量大、断裂能大、可生物降解、生物相容性好、保湿性好、轻盈等其它合成高性能纤维所无法比拟的优良机械性能及特性.为此,本研究对蜘蛛丝的组成、结构、机械性能、纺丝机理、应用前景进行了概述.     

浅谈蜘蛛丝的研究进展情况

蜘蛛丝纤维的来源与组成、性能,在医疗、军事、纺织制衣的应用,综述了国内外利用生物技术和基因工程对蜘蛛丝的研究进展。     

大腹圆珠牵引丝的结构与性能分析

以大腹圆珠牵引丝为研究对象,分析了蜘蛛丝的聚集态结构特征和形态结构特征。在结构研究的基础上,探索和分析了蜘蛛丝高强度和超收缩性能的形成机理。     

Liquid crystalline spinning of spider silk

Spider silk has outstanding mechanical properties despite being spun at close to ambient temperatures and pressures using water as the solvent. The spider achieves this feat of benign fibre processing by judiciously controlling the folding and crystallization of the main protein constituents, and by adding auxiliary compounds, to create a composite material of defined hierarchical structure. Because the 'spinning dope' (the material from which silk is spun) is liquid crystalline, spiders can draw it during extrusion into a hardened fibre using minimal forces. This process involves an unusual internal drawdown within the spider's spinneret that is not seen in industrial fibre processing, followed by a conventional external drawdown after the dope has left the spinneret. Successful copying of the spider's internal processing and precise control over protein folding, combined with knowledge of the gene sequences of its spinning dopes, could permit industrial production of silk-based fibres with unique properties under benign conditions.     

Molecular architecture and engineering of spider dragline silk protein

Spider dragline silk, which is produced in spider major ampullate gland, is a composite proteinacious fiber with highly repetitive Ala-Gly-rich domain. The unique combination of both high tensile strength and high elasticity makes spider dragline silk superior to almost any other natural or synthetic fibers. Cloning of the genes reveals that the silk is composed of at least two major proteins. Each protein component contains multiple repeats of modular structures that alternate between Ala-rich domains and Gly-rich domains. Molecular engineering not only opens a door to the production of spidroins but also provides a valuable experimental system to test and further establish the relationship between modular structures and mechanical properties. Here, based on our own studies, we review the latest progress of the modular structure and genetic engineering and outline the future prospects.     

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 sil...     

Solid-state NMR determination of the secondary structure of Samia cynthia ricini silk

Silks are fibrous proteins that form heterogeneous, semi-crystalline solids. Silk proteins have a variety of physical properties reflecting their range of functions. Spider dragline silk, for example, has high tensile strength and elasticity, whereas other silks are better suited to making housing, egg sacs or the capture spiral of spiders' webs. The differing physical properties arise from variation in the protein's primary and secondary structure, and their packing in the solid phase. The high mechanical performance of spider dragline silk, for example, is probably due to a beta-sheet conformation of poly-alanine domains, embedded as small crystallites within the fibre. Only limited structural information can be obtained from diffraction of silks, so further characterization requires spectroscopic studies such as NMR. However, the classical approach to NMR structure determination fails because the high molecular weight, repetitive primary structure and structural heterogeneity of solid silk means that signals from individual amino-acid residues cannot be resolved. Here we adapt a recently developed solid-state NMR technique to determine torsion angle pairs (phi, psi) in the protein backbone, and we study the distribution of conformations in silk from the Eri silkworm, Samia cynthia ricini. Although the most probable conformation in native fibres is an anti-parallel beta-sheet, film produced from liquid directly extracted from the silk glands appears to be primarily alpha-helical.     

Structure and Properties of Silk Fibers Grafted with Vinyl Siloxane Monomer

IntroductionSilk are used extensively in textile field because of itsexcellent characteristics , but silk crease and yellow easily .Grafting of silk fibers with vinyl monomers is considered asan effective method to substantially i mprove its intrinsicproperties . The most popular vinyl monomers currently usedare methyl methacrylate[1 ,2], hydroxypropyl methacrylate[3]and methacrylamide[4]etc .. The properties of silk fibersgrafted with these monomers were i mproved . But thephysical propertie…     

Physical Properties of Muga Silk and Its Application Potential in Biomaterials

The paper investigated the physical properties of muga silk. Surface properties, linear density, moisture regain and mechanical properties of muga silk were tested before and after degumming. The results show that muga silk has tiny fineness and high strength. The average fineness and the strength of the monofilament are 1. 52 dtex and5.62 c N/dtex, respectively. This makes up for the shortcomings of other kinds of silk,and has great potential in the application of biomaterials.     

紬丝包芯纺纱的探索

本文介绍了一般的包芯纱,包绕纱中纤维的组合形式、纺纱方法及成纱特点。在此基础上介绍了(纟由)丝包芯纺纱的工艺、试验所用的材料、成纱品质及其与(纟由)丝的比较。从而指出(纟由)丝包芯纱兼备了(纟由)丝和化纤长丝的特点。因此,(纟由)丝包芯纺纱有继续探索的必要和可能。     

Surprising strength of silkworm silk

Commercial silkworm silk is presumed to be much weaker and less extensible than spider dragline silk, which has been hailed as a 'super-fibre'. But we show here that the mechanical properties of silkworm silks can approach those of spider dragline silk when reeled under controlled conditions. We suggest that silkworms might be able to produce threads that compare well with spider silk by changing their spinning habits, rather than by having their silk genes altered.     

Preparation and Characterization of Silk Fibroin Aerogel

Silk protein fibroin,as a biomedical material,has good biocompatibility,biodegradability,regulation and excellent physical and chemical properties. In this work,a low density porous silk fibroin material is prepared from fibroin solution by high-speed shearing with impeller. By adjusting shear rate of the stirrer,silk fibroin aerogel with different sizes of the aperture is prepared. In general, this aerogel has small porosity, uniform pores, good mechanical properties and slow rate of degradation. It is observed that increasing the shear rate results in higher porosity of aerogel,while the diameter of the aerogel becomes smaller. This silk aerogel may offer a new option as biomaterial for the tissue engineering application based on the information on the structural behaviors.