Nucleophilic modification of flavonoids for enhanced solubility and photostability towards uniform colouration,bio-activation and ultraviolet-proof finishing of silk fabric

This study targets on the molecular-decoration of flavonoids (FLs) with a reactive ultraviolet absorber (UV-ABS) to enhance their low-solubility and photo-sensitivity, further serving for uniform and ultraviolet (UV)-proof treatment of silk. Quercetin (QUE) and rutin (RUT) showing structural discrepancy in disaccharide moiety are compared. The chemical structures of modified flavonoids (MOD-FLs), adsorption behaviour/mechanism of MOD-FLs on silk, and the colour features and functionalities of treated silk were explored. Results reveal that the absorbance of FLs in water significantly increases after modification indicating the enhanced solubility, which is reconfirmed by the water/n-butanol phase separation experiment. Two intense adsorption bands of MOD-FLs in UVA/UVB range imply their potential use as UV-proof finisher for textile. The exhaustion of MOD-FLs on silk gradually descends as pH increases. MOD-FLs display a closer trend to Psuedo 2nd-order kinetic model than FLs indicating the dominance of chemical adsorption due to the ionic nature of UV-ABS part. MOD-QUE show superior building-up property than MOD-RUT on silk, which is beneficial to achieving diverse intensity of colour and functionality on silk. Fewer aggregates of MOD-FLs are observed on silk surface than FLs. After modification, the colour fading of QUE and RUT treated silk after 8 h light exposure significantly reduce by 71.96% and 42.91%, respectively. MOD-FLs treated silk disinfect over 80 % of E. coli and S. aureus. However, a significant antioxidant decrease of FLs occurs after modification. MOD-FLs (5% owf) imparts silk with high UPF values (50+). In general, the strategy for enhancing the water solubility and photostability of FLs is developed to better serve as bio-based modifiers for textile which is also transferable to the modification of other natural molecules.     

一种天然纳米纤维捕鸟蛛丝的物理化学结构表征

蜘蛛丝作为功能性结构材料, 其独特的纤维成型方法与优良的结构和性能引起许多人的关注. 从20世纪80年代开始有关蜘蛛丝的研究报道日益增加[1]. 与高温高压下或由溶剂纺丝成型的合成纤维相比, 蜘蛛丝在空气中凝固成型, 丝纤维成型安全、无害, 从腹部若干不同吐丝器产生不同种类的丝具有不同的用途[2]. 蜘蛛拖曳丝(dragline silk)的比强度大于钢丝, 且具有较大的断裂伸长率(9%～30%)[3,4], 抗张强度1.1～1.4 GPa. 在相对湿度50%和应变速率100%/min的条件下, 模量值可达10～50 GPa. 在所有已知纤维品种中, 蜘蛛丝的断裂能是最高的. 此外, 蜘蛛丝在许多方面的综合性能优于最优良的人造纤维. 另外, 蜘蛛丝的细度为已知纤度最小的天然有机纤维, 这种高性能丝具有捕捉昆虫甚至鸟类的功能, 因此蜘蛛丝是具有特异功能的天然纤维材料. 目前, 蜘蛛丝结构和性能的研究主要包括其化学组成[5]、结晶结构[6,7]、结构模型[8,9]以及其NMR表征[10]等, 这些研究揭示了蜘蛛丝的氨基酸组成、分子量及其分布、结晶度、晶胞尺寸、链构象以及结构模型等. 这些研究主要集中在少数几种蜘蛛品种上, 如金色圆网织网蛛(Nephila clavipes)、十字圆蛛(A.diadematus)和大腹圆蛛(A.ventrocosus)等. 目前, 已知的蜘蛛种类大于30 000种[11], 以蜘蛛丝为例的生物大分子材料研究是一个挑战性的课题. 国内蜘蛛丝的研究仅有大腹圆蛛拖曳丝蛋白一级结构的研究报道[12,13]. 本文报道了广西捕鸟蛛丝的红外光谱、形貌结构和原子力显微镜的初步研究结果.     

蚕丝蛋白与类动物丝蛋白聚合物共混膜的振动光谱研究

蚕丝纤维具有优良的力学性能 ,不同的环境条件对其力学性能有一定的影响 ,但其力学性能主要取决于形成纤维过程中所形成的以分子链 β-折叠结构及其沿纤维轴方向高度取向为特征的丝纤维凝聚态结构 [1,2 ] .因此在丝纤维的形成及丝蛋白膜的人工制备过程中 ,丝蛋白分子链的构象及其构象转变一直是研究的重点[3～ 6 ] .以蚕丝蛋白 (Silk Fibroin,SF)稀溶液在常温下浇铸的 SF膜一般以无规线团 /α-螺旋为主的构象状态存在 ;经热处理、极性溶剂 (如甲醇等 )处理、应力作用或共混入一些能与SF形成分子间氢键的聚合物组分后 ,SF膜的构象将从无…     

环氧化合物与丝素蛋白化学交联凝胶的结构

对丝素蛋白水溶液与环氧化合物交联剂(PGDE)反应制备的丝素凝胶(CFG)的结构进行了研究.用位相差显微镜观察到CFG具有整体均一的形态结构,而未经PGDE交联的纯丝素凝胶(FG)为颗粒聚集结构.CFG的红外吸收光谱在1104cm^-1处出现PGDE分子中烷醚的吸收峰,而没有出现PGDE两端环醚的特征吸收峰,显示PGDE已经开环交联在丝素蛋白上.氨基酸分析结果显示,酪氨酸、组氨酸和赖氨酸的含量与反应前相比明显减少,PGDE在这些位点与丝素蛋白发生了交联反应.固体¹³CNMR谱观察到酪氨酸羟苯基上的碳发生了化学位移,进一步证实了酪氨酸残基与PGDE发生了化学交联.研究表明,PGDE与丝素蛋白交联形成了分子间交联网络结构,从而使CFG成为较为匀质的凝胶,并有较好的透明度和柔韧性.     

Study on novel eco-friendly anti-creasing agents for natural silk fabric

Three novel eco-friendly anti-creasing agents have been designed and synthesized.The natural silk fabrics treated with them exhibit higher wrinkle recovery degree,strength retention rate and whiteness than those finished with 1,2,3,4-butane tetracarboxylic acid(BTCA).The washing durability of the fabrics treated with the synthesized compounds and BTCA is similar.The chlorine atom.the carboxyl and the s-triazine ring in the synthesized structures and the surface roughness of the silk fabric are all contributive to the improvement of the crease resistance of silk.     

蚕体内不同丝腺部位丝蛋白溶液结构与性质的研究

采用偏光显微镜研究了蚕体内不同丝腺部位(包括前部、中部和后部)中丝蛋白溶液的性质变化,并采用了拉曼光谱和旋转流变仪对中部丝腺(包括前区、中区及后区)的丝蛋白分子结构和流变性能进行了分析。结果发现:蚕体内只有前部丝腺及中部丝腺前区的丝蛋白溶液具有偏光现象;丝蛋白溶液在由中部丝腺后区向前区流动的过程中,粘度及弹性均逐渐变小,其构象则由无规卷曲逐渐向α-螺旋转变,并进一步形成β-折叠构象。由此表明,在蚕体内中部丝腺前区的丝蛋白溶液很可能已经形成了液晶态结构。     

明代潞绸业的兴盛与管理

潞商是晋商的重要分支.明代潞商的商业活动以长治、潞州卫、高平、沁水、阳城等县的丝织业最为出名,明政府曾在潞州设织造局,具体负责监管潞绸的生产、调剂、解运、上贡等事宜.     

塞人及其与草原丝绸之路的开拓

塞人是古代生活在伊犁河流域、伊塞克湖沿岸以及中亚、西亚广大地区的游牧民族的总称。塞人分布地域广阔、构成成分复杂、生活方式独特、风俗习惯怪异。塞人的迁徙对草原丝绸之路的开拓起了十分重要的作用。塞人是最早沟通中西交通的使者之一。     

Preparation and Characterization of Nano-Se/Silk Fibroin Colloids

A solution-phase approach to the synthesis of nano-Se/silk fibroin colloids(NSeSFC) by reducing selenious acid solution with silk fibroin(SF) was proposed, and the composites were in situ prepared by macrowave method. The nanocomposites were characterized with ultraviolet-visible(UV-Vis) absorption spectrometry, resonance Rayleigh scattering(RRS) spectrometry and transmission electron microscopy(TEM). The nano-Se(0) solution exhibited the strongest resonance Rayleigh scattering at 579 nm. Through the RRS di...     

Dual-functional composite with anticoagulant and antibacterial properties based on heparinized silk fibroin and chitosan

Heparinized biomaterials exhibit great anticoagulant properties. However, they promote proliferation of Staphylococcus aureus (S. aureus) and therefore cause infection within the bloodstream upon implantation in vivo. In the present study, an interesting dual-functional composite with anticoagulant and antibacterial properties based on heparinized silk fibroin and chitosan was synthesized. First, heparin was grafted onto the silk fibroin by covalent immobilization with N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS). All data gathered from Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and elemental analysis (EA) indicated that the heparin was successfully immobilized onto the silk fibroin. The dual-functional composite of heparinized silk fibroin and chitosan was then fabricated by a blending method. The anticoagulant activity of the heparinized materials was evaluated using the prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT). The results showed that both heparinized silk fibroin and the composite material exhibited better hemocompatibility in comparison with single silk fibroin or chitosan. The antibacterial property of the materials was investigated by the pour-plate method. Results further suggested that the composite antibacterial property with respect to S. aureus was significantly enhanced. The dual-functionality of the composite material may supply a potential choice in blood contact devices.