Faculty of Mechanical Engineering, Micro- and Nanofluidics Laboratory, Technion-Israel Institute of Technology, Technion City, 32000, Israel.
Small. 2021 Apr;17(17):e2007819. doi: 10.1002/smll.202007819. Epub 2021 Mar 12.
Recent studies on electrically powered active particles that can both self-propel and manipulate cargo load and release, have focused on both spherically shaped Janus particles (JP) and on a parallel electrically conducting plates setup. Yet, spherically shaped JPs set a geometrical limitation on the ability to smartly design multiple dielectrophoretic traps on a single active particle. Herein, these active carriers are extended to accommodate any desired shape and selective metallic coating, using a standard photolithography method. The resulting designed positive and negative dielectrophoretic traps of controlled size, location, and intensity, performed as sophisticated active carriers with a high level of control over their mobility and cargo loading. In addition to cargo loading, the engineered particles exhibit interesting motion in an electrically insulating substrate setup, with in-plane electric field, and, in particular, a tilt angle, and even flipping, that strongly depended on the field frequency and amplitude, hence, exhibiting a much more diverse and rich behavior than spherical JP. The engineered self-propelling carriers are expected to open up new possibilities for unified, label-free and selective cargo loading, transport, and delivery of complex multi-particles.
最近的研究集中在能够自主推进和操纵货物负载以及释放的电动主动粒子上，这些研究既关注了球形的 Janus 粒子（JP），也关注了平行的导电板设置。然而，球形 JP 在智能设计单个主动粒子上的多个介电泳陷阱的能力方面存在几何限制。在此，使用标准的光刻法将这些主动载体扩展到可容纳任何所需形状和选择性金属涂层。由此产生的设计的正、负介电泳陷阱具有可控的尺寸、位置和强度，作为复杂的主动载体表现出高度的可移动性和货物装载控制能力。除了货物装载外，工程粒子在具有平面电场的电绝缘基板设置中表现出有趣的运动，特别是在倾斜角度下，甚至翻转，这强烈依赖于电场的频率和幅度，因此表现出比球形 JP 更加多样和丰富的行为。预计这些工程自推进载体将为统一、无标记和选择性的货物装载、运输和复杂多颗粒的输送开辟新的可能性。
