Huang Tao, Gobeil Sophie, Wang Xu, Misko Vyacheslav, Nori Franco, De Malsche Wim, Fassbender Jürgen, Makarov Denys, Cuniberti Gianaurelio, Baraban Larysa
Max Bergmann Center of Biomaterials and Institute for Materials Science, Technische Universität Dresden, 01062 Dresden, Germany.
Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research, Bautzner Landstrasse 400, 01328 Dresden, Germany.
Langmuir. 2020 Jun 30;36(25):7091-7099. doi: 10.1021/acs.langmuir.0c00012. Epub 2020 Feb 13.
Synthetic nano- and micromotors interact with each other and their surroundings in a complex manner. Here, we report on the anisotropy of active-passive particle interaction in a soft matter system containing an immobile yet photochemical Ag/AgCl-based Janus particle embedded in a dense matrix of passive beads in pure water. The asymmetry in the chemical gradient around the Janus particle, triggered upon visible light illumination, distorts the isotropy of the surrounding electric potential and results in the repulsion of adjacent passive beads to a certain distance away from the Janus particle. This exclusion effect is found to be anisotropic with larger distances to passive beads in front of the Ag/AgCl cap of the Janus particle. We provide insight into this phenomenon by performing the angular analysis of the radii of exclusion and tracking their time evolution at the level of a single bead. Our study provides a novel fundamental insight into the collective behavior of a complex mixture of active and passive particles and is relevant for various application scenarios, e.g., particle transport at micro- and nanoscale and local chemical sensing.
合成纳米和微米马达以复杂的方式相互作用及其周围环境。在这里，我们报道了在一个软物质系统中，活性-被动粒子相互作用的各向异性，该系统包含一个固定在纯水中被动珠子密集基质中的基于光化学Ag/AgCl的Janus粒子。在可见光照射下，Janus粒子周围化学梯度的不对称性会扭曲周围电势的各向同性，并导致相邻被动珠子被排斥到离Janus粒子一定距离处。发现这种排斥效应是各向异性的，在Janus粒子Ag/AgCl帽前方的被动珠子距离更大。我们通过对排斥半径进行角度分析并跟踪单个珠子水平上它们的时间演化，深入了解了这一现象。我们的研究为活性和被动粒子复杂混合物的集体行为提供了新的基本见解，并且与各种应用场景相关，例如微纳尺度的粒子传输和局部化学传感。
