Zhu Qirong, Cohen Sidney R, Brontvein Olga, Fransson Jonas, Naaman Ron
Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, 76100, Israel.
Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 76100, Israel.
Small. 2024 Nov;20(48):e2406631. doi: 10.1002/smll.202406631. Epub 2024 Aug 29.
Superparamagnetic iron oxide nanoparticles (SPIONs) have attracted wide attention due to their promising applications in biomedicine, chemical catalysis, and magnetic memory devices. In this work, the force is measured between a single SPION coated with chiral molecules and a ferromagnetic substrate by atomic force microscopy (AFM), with the substrate magnetized either toward or away from the approaching AFM tip. The force between the coated SPION and the magnetic substrate depends on the handedness of the molecules adsorbed on the SPION and on the direction of the magnetization of the substrate. By inserting nm-scale spacing layers between the coated SPION and the magnetic substrate it is shown that the SPION has a short-range magnetic monopole-like magnetic field. A theoretical framework for the nature of this field is provided.
超顺磁性氧化铁纳米颗粒（SPIONs）因其在生物医学、化学催化和磁存储设备等领域的潜在应用而备受关注。在这项工作中，通过原子力显微镜（AFM）测量了涂覆有手性分子的单个SPION与铁磁基底之间的力，基底的磁化方向要么朝向接近的AFM针尖，要么远离。涂覆的SPION与磁性基底之间的力取决于吸附在SPION上的分子的手性以及基底的磁化方向。通过在涂覆的SPION和磁性基底之间插入纳米级间隔层，表明SPION具有短程类磁单极子磁场。并提供了该磁场性质的理论框架。
