Magnetic chains are of fundamental and technological interest. However, 1D assemblies of magnetic nanoparticles are only metastable such that their controlled organization requires the use of templates. Bacteriophages are human-inoffensive viruses with a filamentous morphology that have been shown to exhibit great potential in materials research. Here, we thus utilized the M13 phage as a model for the formation of actuated magnetite nanoparticle superstructures. First, we built a sperm-like ensemble by covalently attaching magnetic nanoparticles to the head of the phage. Second, chain-like assemblies are obtained based on the electrostatic interactions between positively-charged magnetite nanoparticles attached to the negatively-charged phage surface. The nanoparticles-phages assembly is steered by external magnetic fields. We anticipate such materials can find applications in nanotechnology or nanomedicine.

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磁性纳米颗粒的噬菌体模板组装及其驱动潜力

磁链具有基本和技术意义。然而，磁性纳米粒子的一维组装只是亚稳态，因此它们的受控组织需要使用模板。噬菌体是一种对人类无害的病毒，具有丝状形态，已被证明在材料研究中表现出巨大的潜力。在这里，我们因此利用 M13 噬菌体作为形成驱动磁铁矿纳米颗粒超结构的模型。首先，我们通过将磁性纳米粒子共价连接到噬菌体的头部来构建一个类似精子的集合。其次，基于附着在带负电荷的噬菌体表面的带正电荷的磁铁矿纳米颗粒之间的静电相互作用获得链状组件。纳米颗粒-噬菌体组装由外部磁场控制。