合成纳米银微生物的研究进展

从不同来源角度对具有纳米银合成能力的微生物进行对比分析.主要针对4大类微生物来源,即矿物来源、海洋来源、植物与土壤来源以及其他来源,归纳总结各来源微生物还原制备纳米银的研究进展以及不同来源的优缺点.进一步对不同微生物的还原机理进行总结分析,还原机理包括胞内酶还原和其他胞内物质,例如多糖、多肽、吡啶等还原.最后,对合成纳...     

纳米银敷料无菌检查方法

依据《中国药典》2005年版二部附录无菌检查法进行试验,建立适合于纳米银敷料的无菌检查方法。采用直接接种法,对14批纳米银敷料进行无菌方法学验证,结果表明使用规格40mL的培养基、每管培养基接种量为1cm×3cm时,纳米银敷料无明显抑菌作用,可按此方法进行无菌检查。     

纳米银的制备及应用

金属纳米材料是纳米材料的一个重要方面,近几年,纳米银因其有着特殊应用成为金属材料研究的热点.综述了纳米银的制备方法及其应用.     

The Efficiency of Application Nanosilver in Technological Processes of Making Red Wine

The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine material of red grape variety ＂Saperavi＂. After completion of malolactic fermentation, the second racking the wine material off the lees and its treatment with antiseptics were carried out. Sulfur dioxide （Kadifit） and different doses of nanostructured silver were used. Microbiological investigation was performed on the presence of lactic bacteria after completion of malolactic fermentation and racking off the lees. The investigation of phenolic compounds was conducted at the following stages of technological processes： （1） after completion of alcoholic fermentation and racking off the lees; （2） after completion of malolactic fermentation; （3） after the second racking off the lees and treatment with antiseptics. By means of the HPLC analysis, the amounts ofcatechins, phenolcarbonic acids and flavonols were determined. It has been established that after conduction of malolactic fermentation in the process of racking the wine material off the lees and storage, the application of 0.6 mg/L of nano-silver for blocking of lactic-acid bacteria and inhibition of oxidation of phenolic compounds has the same effect as sulfitization with 50 mg/L of Kadifit.     

Antimicrobial nanomaterials for water disinfection and microbial control: potential applications and implications

The challenge to achieve appropriate disinfection without forming harmful disinfection byproducts by conventional chemical disinfectants, as well as the growing demand for decentralized or point-of-use water treatment and recycling systems calls for new technologies for efficient disinfection and microbial control. Several natural and engineered nanomaterials have demonstrated strong antimicrobial properties through diverse mechanisms including photocatalytic production of reactive oxygen species that damage cell components and viruses (e.g. TiO2, ZnO and fullerol), compromising the bacterial cell envelope (e.g. peptides, chitosan, carboxyfullerene, carbon nanotubes, ZnO and silver nanoparticles (nAg)), interruption of energy transduction (e.g. nAg and aqueous fullerene nanoparticles (nC(60))), and inhibition of enzyme activity and DNA synthesis (e.g. chitosan). Although some nanomaterials have been used as antimicrobial agents in consumer products including home purification systems as antimicrobial agents, their potential for disinfection or microbial control in system level water treatment has not been carefully evaluated. This paper reviews the antimicrobial mechanisms of several nanoparticles, discusses their merits, limitations and applicability for water disinfection and biofouling control, and highlights research needs to utilize novel nanomaterials for water treatment applications.     

纳米银涂膜对微波冻干鲍鱼微生物的影响

为控制鲍鱼微波冻干过程中微生物数量,试验过程中将鲍鱼进行纳米银涂膜。实验结果表明,在微波冻干过程中,以0.3 mg/L的纳米银淀粉液涂膜,鲍鱼中细菌总数下降99.2%,大肠菌群MPN值小于30。微波和纳米银涂膜结合,很好的控制了冻干鲍鱼的微生物,而且纳米银涂膜对鲍鱼的干燥效率无明显影响。     

Sol-gel synthesized Sr4Al14O25:Eu2+/Dy3+ blue–green phosphorous as oxygen sensing materials

In this study, we utilized newly synthesized Sr₄Al₁₄O₂₅:Eu²⁺/Dy³⁺ blue–green phosphors along with silver nanoparticles (AgNPs) for fabrication of oxygen sensitive materials. To the best of our knowledge oxygen sensing mechanism of the offered design is totally different from the previously published works. One-component silicone: poly (1-trimethylsilyl-1-propyne), two component phenyl bearing silicone, plasticized polymethylmethacrylate, and ethylcellulose (EC) were tested as matrix materials. Electrospun fibers, porous and smooth thin films were produced by electrospinning or knife coating technique. Oxygen induced luminescence of the phosphors at 544 nm was followed as the analytical signal. Utilization of silver nanoparticles in silicone along with phosphors resulted with a 7.14 fold enhancement in the signal intensity and significant spectral response towards oxygen competing with the signals of the oxygen sensors utilizing metalloporphyrins or ruthenium complexes. We observed high sensitivity and stability, increased surface area and an enhancement in all sensor dynamics. Linearity of the calibration plots was superior for the pO₂ range of 0.0–20.0% with respect to the previously reported ones. When stored at the ambient air of the laboratory there was no significant drift in signal intensity after 12 months. Our sensitivity and stability tests are still in progress.     

可见分光光度法测定纳米银溶液的银含量及其应用

采用可见分光光度法快速测定耐尔（R）纳米银溶液的银含量.试验表明,在408 nm处,纳米银溶液的吸光度与溶液中的银含量在2～ 10 mg/L范围内呈良好的线性关系,相对标准偏差为0.07％ ～ 0.22％,回收率为98.30％ ～ 104.44％.应用于浸渍法医用载银抗菌粘胶纤维的制备,通过测定纳米银溶液处理粘胶纤维前后溶液的吸光度变化,计算医用载银抗菌粘胶纤维的银含量与电感耦合等离子发射光谱,测试结果基本一致.     

真丝织物的汽蒸法纳米银抗菌整理

为了实现真丝织物的抗菌性能,以一种含有多胺基化合物(RSD)和硝酸银的混合整理液对真丝织物进行处理,并采用汽蒸法在位还原得到纳米银抗菌真丝织物.对纳米银抗菌真丝织物表面纳米银的形成、纳米银的形态、纳米银的含量、纳米银抗菌真丝织物的白度、抗菌性能和耐久性能等进行了测试与分析.结果表明,当纳米银含量为81.65 mg/kg时,对金黄色葡萄球菌和大肠杆菌的抗菌率分别达99.49%和99.98%,洗涤50次后,对金黄色葡萄球菌和大肠杆菌的抗菌率仍保持在97.43%以上;纳米银抗菌真丝织物的白度影响较小.     

纳米银/PAMPS复合物的微波合成及表征

在不加还原剂的条件下,微波辐射双原位合成纳米银/2-丙烯酰胺基-2-甲基丙磺酸均聚物[PAMPS]复合材料。并通过UV-Vis、XRD、FTIR、TEM、XPS和TG等分析方法对其进行表征。结果表明:纳米银粒子具有面心立方结构,且较均匀地分散在聚合物基体中;微波辐射时间不影响纳米银粒子的形态;纳米银与基体PAMPS中的氮原子和羰基氧原子存在相互作用,而且对基体PAMPS的热学性能有很大影响。