Ag-decorated Fe3O4@SiO2 core-shell nanospheres: Seed-mediated growth preparation and their antibacterial activity during the consecutive recycling
Ag-decorated Fe3O4@SiO2 core-shell nanospheres: Seed-mediated growth preparation and their antibacterial activity during the consecutive recycling
复制标题
Ag修饰的Fe3O4@SiO2核壳纳米球：种子介导的生长制备及其在连续回收过程中的抗菌活性
DOI：
10.1016/j.jallcom.2016.03.191
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发表时间：
2016-08-15
影响因子：
6.2
通讯作者：
Zhang, Yong
中科院分区：
文献类型：
--
作者：
Li, Miaomiao;Wu, Wenjie;Zhang, Yong
我们展示了一种种子介导生长方法，用于在不使用表面功能化的情况下合成银纳米粒子修饰的Fe₃O₄@SiO₂核壳纳米球。通过调节添加的硝酸银浓度以及种子介导生长过程中的交替重复次数，可以调节固定在SiO₂表面的银纳米粒子的粒径和修饰密度。所制备的银修饰的Fe₃O₄@SiO₂纳米球对大肠杆菌、枯草芽孢杆菌和白色念珠菌表现出优异的抗菌活性，其最小抑菌浓度分别为12.5μg/mL、50μg/mL和50μg/mL。据推测，它们的抗菌活性归因于释放的银离子与重要酶和蛋白质的官能团的相互作用，以及银纳米粒子中光生电子作用下产生的活性氧物质的强氧化性。除了研究它们的抗菌机制外，我们还研究了这些异质结构纳米球在连续磁分离和回收过程中抗菌活性的变化。结果表明，磁性抗菌剂可以重复使用，即使经过9次循环其活性仍然稳定，这使其有望应用于生物医学领域。（C）2016爱思唯尔B.V.保留所有权利。
We demonstrated a seed-mediated growth approach to synthesize Ag nanoparticles-decorated Fe3O4@SiO2 core-shell nanospheres without use of surface functionalization. The particle size and decoration density of the immobilized Ag nanoparticles on SiO2 surface were tunable by adjusting the added AgNO3 concentration and the alternating repetition times in seed-mediated growth procedure. The as-prepared Ag-decorated Fe3O4@SiO2 nanospheres exhibited excellent antibacterial activities against Escherichia coli, Bacillus subtilis and Candida albicans, in which the minimum inhibitory concentration were 12.5 mu g mL(-1), 50 mu g mL(-1) and 50 mu g mL(-1), respectively. It is speculated that their antibacterial activity is attributed to both the interaction of released Ag ions with the functional groups of vital enzymes and proteins and the strong oxidation of reactive oxygen species generated under the action of photoinduced electrons in Ag nanoparticles. Besides studying their antibacterial mechanism, we also investigated the variation of antibacterial activity of these heterostructured nanospheres during the consecutive magnetic separation and recycling. It shows that the magnetic antibacterial agent could be reused and its activity remained stable even after nine cycles, which enable it to be promisingly applied in biomedical areas. (C) 2016 Elsevier B.V. All rights reserved.