Here, we describe the magnetic actuation of soft shuttles for open-top microfluidic applications. The system is comprised of two immiscible liquids, including glycerol as the soft shuttle and a suspension of iron powder in sucrose solution as the magnetic drop. Permanent magnets assembled on 3D printed motorized actuators were used for the actuation of the magnetic drop, enabling the glycerol shuttle to be propelled along customized linear, circular, and sinusoidal paths. The dynamics of the hybrid shuttle–magnetic drop system was governed by the magnetic force, the friction at the interface of the shuttle and the substrate, and the surface tension at the interface of the shuttle and the magnetic drop. Increasing the magnetic force leads to the localized deformation of the shuttle and eventually the full extraction of the magnetic drop. The versatility of the system was demonstrated through the propelling of the shuttle across a rough surface patterned with microfabricated barriers as well as taking advantage of the optical properties of the shuttle for the magnification and translation of microscale characters patterned on a planar surface. The integration of the system with current electrowetting actuation mechanisms enables the highly controlled motion of the magnetic drop on the surface of a moving shuttle. The simplicity, versatility, and controllability of the system provide opportunities for various fluid manipulation, sample preparation, and analysis for a range of chemical, biochemical, and biological applications.

中文翻译：

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软梭的电磁驱动和变形。

在这里，我们描述了用于开顶微流体应用的软梭的磁致动。该系统由两种不混溶的液体组成，包括甘油（作为软梭）和铁粉在蔗糖溶液中的悬浮液（作为磁滴）。使用组装在3D打印的电动执行器上的永磁体来驱动磁滴，从而使甘油梭可以沿着定制的线性，圆形和正弦曲线路径推进。混合梭－磁滴系统的动力学受磁力，梭与基底的界面处的摩擦以及梭与磁滴的界面处的表面张力的控制。磁力的增加会导致航天飞机的局部变形，并最终导致磁滴的完全提取。该系统的多功能性通过航天飞机在带有微细加工的障碍物图案的粗糙表面上的推动以及利用航天飞机的光学特性来放大和平移图案化在平面上的微型字符而得到证明。该系统与当前的电润湿致动机构的集成使移动的梭子表面上的磁滴高度受控地运动。系统的简单性，多功能性和可控制性为各种化学，生化和生物学应用提供了各种流体处理，样品制备和分析的机会。