Self‐Propulsion and Shear Flow Align Active Particles in Nozzles and Channels
Self‐Propulsion and Shear Flow Align Active Particles in Nozzles and Channels
复制标题
DOI：
10.1002/aisy.202000178
复制
发表时间：
2020-11
影响因子：
7.4
通讯作者：
Leonardo Dominguez Rubio;M. Potomkin;R. Baker;Ayusman Sen;L. Berlyand;I. Aranson
中科院分区：
文献类型：
--
作者：
Leonardo Dominguez Rubio;M. Potomkin;R. Baker;Ayusman Sen;L. Berlyand;I. Aranson
活性粒子消耗储存在环境中的能量，并将其转化为机械运动。这些系统的许多潜在应用涉及它们通过通道和喷嘴的流动、挤出和沉积，例如靶向药物递送和非平衡自组装。然而，理解它们与流动和边界的基本相互作用仍然是不完整的。在此，实验和理论研究过氧化氢（H2O2）供电的自推进金铂纳米棒在平行通道和喷嘴进行。主动（自推进）和被动杆的行为进行了系统的比较。研究发现，大多数活性杆在高剪切区域与流线自对准，并表现出趋流性（逆流游泳）。相比之下，被动杆继续不受影响地移动，直到流速非常高，此时它们也开始显示出一些对齐。实验结果是合理的计算建模描绘活动和杆流相互作用。所获得的结果提供了深入了解复杂的几何形状的主动颗粒流和挤出的操纵和控制。
Active particles consume energy stored in the environment and convert it into mechanical motion. Many potential applications of these systems involve their flowing, extrusion, and deposition through channels and nozzles, such as targeted drug delivery and out‐of‐equilibrium self‐assembly. However, understanding their fundamental interactions with flow and boundaries remain incomplete. Herein, experimental and theoretical studies of hydrogen peroxide (H2O2) powered self‐propelled gold–platinum nanorods in parallel channels and nozzles are conducted. The behaviors of active (self‐propelled) and passive rods are systematically compared. It is found that most active rods self‐align with the flow streamlines in areas with high shear and exhibit rheotaxis (swimming against the flow). In contrast, passive rods continue moving unaffected until the flow rate is very high, at which point they also start showing some alignment. The experimental results are rationalized by computational modeling delineating activity and rod‐flow interactions. The obtained results provide insight into the manipulation and control of active particle flow and extrusion in complex geometries.