Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO, USA.
Department of Anesthesiology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA.
Sci Rep. 2022 Mar 24;12(1):5078. doi: 10.1038/s41598-022-09177-x.
Microscale bots intended for targeted drug delivery must move through three-dimensional (3D) environments that include bifurcations, inclined surfaces, and curvature. In previous studies, we have shown that magnetically actuated colloidal microwheels (µwheels) reversibly assembled from superparamagnetic beads can translate rapidly and be readily directed. Here we show that, at high concentrations, µwheels assemble into swarms that, depending on applied magnetic field actuation patterns, can be designed to transport cargo, climb steep inclines, spread over large areas, or provide mechanical action. We test the ability of these multimodal swarms to navigate through complex, inclined microenvironments by characterizing the translation and dispersion of individual µwheels and swarms of µwheels on steeply inclined and flat surfaces. Swarms are then studied within branching 3D vascular models with multiple turns where good targeting efficiencies are achieved over centimeter length scales. With this approach, we present a readily reconfigurable swarm platform capable of navigating through 3D microenvironments.
用于靶向药物输送的微型机器人必须能够在包括分叉、倾斜表面和曲率的三维（3D）环境中移动。在之前的研究中，我们已经表明，由超顺磁珠可逆组装的磁驱动胶体微轮（µwheels）可以快速平移并易于控制。在这里，我们表明，在高浓度下，µwheels 会组装成群，根据施加的磁场激励模式，可以设计用于运输货物、爬上陡峭的斜坡、在大面积上扩散或提供机械作用。我们通过在陡峭和平坦表面上对单个µwheels 和µwheels 群的平移和分散进行特征分析，测试了这些多模态群在复杂倾斜微环境中导航的能力。然后，在具有多个转弯的分支 3D 血管模型中研究了 swarm，在这些模型中，在厘米级长度范围内实现了良好的靶向效率。通过这种方法，我们提出了一种易于重新配置的 swarm 平台，能够在 3D 微环境中导航。
