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61.
Olga Mykhaylyk Dialekti Vlaskou Nittaya Tresilwised Pimolpan Pithayanukul Winfrid Möller Christian Plank 《Journal of magnetism and magnetic materials》2007
Newly synthesized magnetic nanomaterials possess high DNA binding capacity either itself or in the presence of a positively charged lipid-based Metafectene™ reagent or branched polyethylene imine 25 kDa. Polyethylene imine (PEI)-modified nanomaterials are able to deliver nucleic acids in cell culture in duplexes. Magnetofection with triplexes of nanomaterials results in higher transduction efficiencies compared to optimal PEI or Metafectene formulations. 90% transient down-regulation of the target protein in HeLa-green fluorescence protein cells was achieved at short interfering RNA concentrations as low as 8 nM with a formulation of PEI-modified nanoparticles. 相似文献
62.
微乳液技术制备纳米材料 总被引:15,自引:0,他引:15
微乳液是表面活性剂、油相和水相形成的热力学稳定的各向同性的单分散体系,其分散质点为纳量级,它为纳米材料的制备提供理想的模板和微环境,介绍微乳液制备纳米材料的方法和影响因素以及微乳液法制备催化剂、超导体、半导体及磁性等材料的研究进展。 相似文献
63.
一维纳米材料在光学、电子学、环境和医学等领域有广泛的应用前景,已成为材料领域研究的热点.本文比较全面地归纳和分析了一维无机纳米材料的最新研究进展,介绍了材料的制备方法、性质和应用,探讨了将来的发展方向. 相似文献
64.
Razium Ali Soomro Ayman Nafady Keith Richard Hallam Sana Jawaid Abdullah Al Enizi Syed Tufail Hussain Sherazi Sirajuddin Zafar Hussain Ibupoto Magnus Willander 《Analytica chimica acta》2016
This study describes sensitive determination of atropine using glassy carbon electrodes (GCE) modified with Co3O4 nanostructures. The as-synthesised nanostructures were grown using cysteine (CYS), glutathione (GSH) and histidine (HYS) as effective templates under hydrothermal action. The obtained morphologies revealed interesting structural features, including both cavity-based and flower-shaped structures. The as-synthesised morphologies were noted to actively participate in electro-catalysis of atropine (AT) drug where GSH-assisted structures exhibited the best signal response in terms of current density and over-potential value. The study also discusses the influence of functional groups on the signal sensitivity of atropine electro-oxidation. The functionalisation was carried with the amino acids originally used as effective templates for the growth of Co3O4 nanostructures. The highest increment was obtained when GSH was used as the surface functionalising agent. The GSH-functionalised Co3O4-modified electrode was utilised for the electro-chemical sensing of AT in a concentration range of 0.01–0.46 μM. The developed sensor exhibited excellent working linearity (R2 = 0.999) and signal sensitivity up to 0.001 μM of AT. The noted high sensitivity of the sensor is associated with the synergy of superb surface architectures and favourable interaction facilitating the electron transfer kinetics for the electro-catalytic oxidation of AT. Significantly, the developed sensor demonstrated excellent working capability when used for AT detection in human urine samples with strong anti-interference potential against common co-existing species, such as glucose, fructose, cysteine, uric acid, dopamine and ascorbic acid. 相似文献
65.
A novel method for synthesizing magnetically recyclable nanocatalyst Fe3O4@Nico@Cu (Nico =nicotinic acid) was introduced. The structural, morphological, and magnetic properties of the nano-catalyst were characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy, and vibrating sample magnetometry. Finally, Fe3O4@Nico@Cu was examined toward the hydrogenation of azo dyes methyl orange, methylene blue, eosin Y, and rho-damine B. The nanocatalyst showed excellent reusability properties that remained unchanged after several catalytic cycles. Therefore, the current findings show the potential of the prepared Fe3O4@Nico@Cu nanocatalyst as a candidate for application in the purification of organic aqueous pollutants for wastewater treatment. 相似文献
66.
纳米催化介于均相催化与多相催化之间, 也称为”半多相催化”, 目前正受到人们越来越多的关注. 最近几年, 应用双金属纳米材料进行催化研究取得了很大进展, 使用这些催化材料可以增加反应活性和选择性, 而且能很好地得以回收. 本文综述了双金属纳米材料催化的各种有机反应, 如选择性氧化/氢化、偶联和其它反应(脱卤、酰胺化、还原氨化、芳基硼酸与烯酮的1,4-不对称加成和氢解). 将双金属纳米材料用于催化合成更加复杂的有机分子值得期待. 在双金属纳米有机催化领域, 基础理论和实际应用尚有较大的发展空间. 未来该领域的发展需要开展多学科的合作, 包括合理设计和可控制备相关的双金属纳米材料、深入理解催化机理及发展计算催化. 相似文献
67.
《Particuology》2022
Manufactured nanomaterials with unique properties have been extensively applied in various industrial, agricultural or medical fields. However, some of the properties have been identified to be closely related to nanomaterial toxicity. The “nano-paradox” has aroused concerns over the use and development of nanotechnology, which makes it difficult for regulatory agencies to regulate nanomaterials. The key to fulfilling proper nanomaterial regulation lies in the adequate understanding of the impact of nanomaterial properties on nano-bio interactions. To this end, we start the present work with a brief introduction to nano-bio interactions at different levels. Based on that, how key toxicity-associated properties of manufactured nanomaterials (i.e., size, shape, chemical composition, surface properties, biocorona formation, agglomeration and/or aggregation state, and biodegradability) impact their toxicokinetics, cellular uptake, trafficking and responses, and toxicity mechanisms is deeply explored. Moreover, advanced analytical methods for studying nano-bio interactions are introduced. Furthermore, the current regulatory and legislative frameworks for nanomaterial-containing products in different regions and/or countries are presented. Finally, we propose several challenges facing the nanotoxicology field and their possible solutions to shed light on the safety evaluation of nanomaterials. 相似文献
68.
采用硝酸铋和硫脲为反应物,通过添加不同的表面活性剂如Triton X-100+OP-10、TX-10、Triton X-100,用回流法合成了硫化铋纳米花。所得产物用XRD、EDS、TEM、SAED、SEM以及UV-Vis进行了表征。结果表明,经85~110 ℃回流反应3 h,可以得到结晶良好、具有各种形貌的正交晶相的硫化铋纳米花。经计算,其晶胞参数为a=0.439 34 nm, b=0.965 64 nm, c=1.118 5 nm。UV-Vis分析表明,硫化铋 相似文献
69.
70.