纳米银在TEMPO催化氧化黄麻纤维上的微波原位合成

金属纳米粒子一纤维素复合材料是一种具有生物相容性和抗菌性的可再生纳米材料,由于其应用功能广泛而备受关注。本文首次研究了不使用还原剂条件下’采用微波原位合成法在丁EMPO（2,2,6,6一四甲基哌啶氧化物自由基）选择性氧化黄麻纤维上简便、快速制备银纳米粒子。微波加热5min,纤维上的银纳米粒子平均尺寸为50．0±2．0hm,而加热10min则为90．0±4．7nm。该多功能黄麻一银纳米粒子复合物具有优异的热稳定性和高结晶度。     

纳米银的可控制备及对棉织物的抗菌整理

利用改性聚酰胺超支化聚合物（PNP）在水溶液中制备纳米银,探讨了其还原、控制制备纳米银的机理,研究了所制备的纳米银水溶液的抗菌性能,并利用PNP在棉织物中原位控制生成纳米银,以实现对棉织物的抗菌整理。结果表明：PNP中的氨基能够主动诱捕、还原银离子,并通过PNP的分子网络结构对纳米银的生成起控制作用。通过调节银离子的量,制备了平均粒径分别为13.23、4.34、2.66 nm的纳米银水溶液,所制备的纳米银水溶液最小抑菌浓度为2 mg/L。利用PNP原位控制生成纳米银整理的棉织物具有优异的抗菌性能,其对金黄色葡萄球菌和大肠杆菌的抑菌率均在99 %以上,并具有优异的耐洗牢度。     

PDDA-Ag吸光光度法测定果粒橙中日落黄含量

目的:建立测定果粒橙中日落黄含量的方法。方法:以聚二烯丙基二甲基氯化铵（PDDA）为稳定剂,Na BH₄为还原剂还原Ag NO₃溶液得到纳米银（Ag）,利用紫外-可见分光光度法研究日落黄对PDDA-Ag吸光度的影响。结果:日落黄对PDDA-Ag紫外吸收强度具有强猝灭作用,据此建立了紫外-可见分光光度法测定日落黄含量的新体系。在最优条件下,PDDA-Ag吸收强度降低值ΔA与日落黄浓度在0.01×10^-69×10^-6mol/L范围内有良好线性关系。该方法用于果粒橙中日落黄的检测,回收率为94%¹08%。结论:该方法可为实际样品中日落黄含量测定提供实验数据和方法参考。      

基于共价结合的纳米银抗菌棉织物研究进展

针对棉织物与纳米银之间缺乏亲和性,主要依靠物理吸附结合,水洗牢度差等问题,总结了基于共价结合的纳米银抗菌棉织物的最新研究进展,探讨了席夫碱反应和酯化反应这2种共价结合机制。以纳米银与棉织物之间的共价交联剂(超支化聚合物、树状大分子、丝素、丝胶、半胱氨酸、蛋氨酸、巯基乙酸、壳聚糖衍生物、聚苯乙烯-b-聚丙烯酸、丁烷四羧酸)种类进行分类介绍,结合抑菌率和银含量的数据讨论了基于共价结合的纳米银抗菌棉织物的制备工艺、抗菌性能和抗菌耐洗性能。最后对基于共价结合的纳米银抗菌棉织物领域存在的不足和未来需要深入关注的地方进行了探讨。研究指出,共价交联法大幅提高了纳米银的抗菌耐洗性能,为开发环境友好和长效抗菌的纳米银纺织品提供了新思路和新途径。     

Facile synthesis of silver nanoparticles using Tribulus longipetalus extract and their antioxidant and antibacterial activities

In this study, the preparation of silver nanoparticles (Ag NPs) using Tribulus longipetalus Viv. leaf extract was evaluated. Additionally, the in vitro antioxidant and antibacterial activities of the extract were evaluated. The antioxidant activity was assessed by two different approaches based on 2,2-diphenyl-1-picryl-hydrazyl and reducing power assay. The antibacterial activity of the extract, on the other hand, was determined against gram positive and gram negative microorganisms. The AgNPs prepared under the optimal conditions were found to be 15 nm in size and were characterized by ultraviolet–visible spectroscopy, dynamic light scattering, X-ray diffraction and transmission electron microscopy.     

In situ synthesis of ZnO Nanoparticles on plasma treated cotton fabric utilizing durable antibacterial activity

In this research work, ZnO nanoparticles (ZnO-NPs) were in situ synthesized by the sonochemical method at room temperature on both untreated and plasma pre-treated cotton woven fabric. Air plasma was used for pre-functionalization of cotton fabric. And the effect of plasma pre-functionalization on the adhesion properties between ZnO nanoparticles and the cotton surface were studied.

The results show that nanoparticles with average sizes of 20–90 nm with different morphologies have been created on the surface of samples. Characterization studies were carried out using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD), and Inductive coupled plasma (ICP). The antibacterial activities of the fabrics were assessed by the colonies count method. The results show that the finished fabric demonstrated significant antibacterial activity against Staphylococcus aureus in the antibacterial test. The wash fastness of both untreated and plasma pre-treated samples after 30 times of washing was investigated. The results showed that the parameters of plasma reactor play a very important role in improving the antibacterial durability.     

In-situ synthesis of CuO nanoparticles on cotton fabrics using spark discharge method to fabricate antibacterial textile

In this research, the spark discharge method (SDM) was used for in-situ synthesis of copper and copper oxide nanoparticles (NPs) on cotton fabrics for producing antibacterial textile. Varieties of analytical techniques were applied for the characterization of both NPs and synthesized CuO NPs on cotton fabrics. The structural characterization of the particles was carried out by the X-ray powder diffraction method. Also, the morphological properties of treated cotton samples were investigated using scanning electron microscope. Particle size and size distribution were measured by dynamic light scattering apparatus. The results show that concentration of 100 ppm is enough for killing 10⁶ CFU/mL of bacteria. It is indicated that the synthesized CuO NPs are very strong against both Staphylococcus aureus and Escherichia coli. Also, the durability of antibacterial efficiency after 15 times of washing was tested. The results confirm that the antibacterial fastness properties are significant and no colonies spread over agar plate after 15 cycles of washing. It was concluded that SDM for in-situ synthesize of nano-CuO on cotton fabrics in batch systems is very promising method.