International Advanced Research Centre for Powder Metallurgy and New Materials, RCI Road, Balapur PO, RR District, Hyderabad 500005, India.
Colloids Surf B Biointerfaces. 2011 Jan 1;82(1):203-8. doi: 10.1016/j.colsurfb.2010.08.039. Epub 2010 Sep 22.
The silica-silver core-shell particles were synthesized by simple one pot chemical method and were employed on the cotton fabric as an antibacterial agent. Extremely small (1-2 nm) silver nanoparticles were attached on silica core particles of average 270 nm size. The optimum density of the nano silver particles was found which was sufficient to show good antibacterial activity as well as the suppression in their surface plasmon resonance responsible for the colour of the core-shell particle for antibacterial textile application. The change in the density and size of the particles in the shell were monitored and confirmed by direct evidence of their transmission electron micrographs and by studying surface plasmon resonance characteristics. The colony counting method of antibacterial activity testing showed excellent results and even the least silver containing core-shell particles showed 100% activity against bacterial concentration of 10(4) colony counting units (cfu). The bonding between core-shell particles and cotton fabric was examined by X-ray photoelectron spectroscopy. The antibacterial activity test confirmed the firm attachment of core-shell particles to the cotton fabric as a result 10 times washed sample was as good antibacterial as that of unwashed sample. The bacterial growth was inhibited on and beneath the coated fabric, at the same time no zone of inhibition which occurs due to the migration of silver ions into the medium was observed indicating immobilization of silver nanoparticles on silica and core-shell particles on fabric by strong bonding.
采用简单的一步化学法合成了硅-银核壳粒子，并将其作为抗菌剂应用于棉织物上。非常小的（1-2nm）银纳米粒子附着在平均尺寸为 270nm 的硅核粒子上。研究发现，纳米银粒子的最佳密度足以显示出良好的抗菌活性，同时抑制了其表面等离子体共振，这是核壳粒子用于抗菌纺织品的颜色的原因。通过透射电子显微镜的直接证据以及研究表面等离子体共振特性，监测和证实了壳层中粒子的密度和尺寸的变化。通过对抑菌活性测试的菌落计数法显示出了极好的结果，甚至是含银量最少的核壳粒子对 10（4）个菌落计数单位（cfu）的细菌浓度也显示出了 100%的活性。通过 X 射线光电子能谱研究了核壳粒子与棉织物之间的结合。抑菌活性测试证实了核壳粒子与棉织物的牢固结合，因此经过 10 次洗涤的样品与未洗涤的样品一样具有良好的抗菌性。在涂层织物上和下方抑制了细菌的生长，同时没有观察到由于银离子迁移到介质中而产生的抑菌区，这表明银纳米粒子在硅和核壳粒子上通过强键合被固定在纤维上。
