(368n) Magnetic Field Enabled Assembly and Propulsion of Colloidal Particles in a Magnetic Medium

Microrobots have the potential for diverse applications, including targeted drug delivery and minimally invasive surgery. Despite advancements in microrobot design and actuation strategies, achieving precise control over their motion remains challenging due to the dominance of viscous drag, system disturbances, physicochemical heterogeneities, and stochastic Brownian forces. This study demonstrates precise control over the interfacial motion of model microellipsoids using rotating magnetic fields. The impacts of microellipsoid aspect ratio, field characteristics, and magnetic properties of the medium and the particle on the motion are investigated. The role of mobile micro-vortices generated in the medium by rotating microellipsoids in capturing, transporting, and releasing model cargo particles in a contactless manner is highlighted. Furthermore, an approach for controlled navigation through mazes based on real-time particle and obstacle sensing, path planning, and magnetic field actuation without human intervention is presented. This study introduces a method to precisely control the motion of microellipsoids and demonstrates their ability to uptake and release cargo on-demand.

Research Interests

As a scientist trained in the fundamentals of chemical engineering, my research focuses on utilizing colloidal particles as functional microrobots, involving an interdisciplinary approach that integrates microtechnology, biochemistry, and control engineering. My expertise spans the fabrication of microrobots and implementing actuation and control strategies for the programmable navigation of microrobots. My interest in this research area stems from the considerable application potential of microrobots in the biomedical area, such as drug delivery.

Additionally, I have also investigated the application of magnetic fields to manipulate colloidal interactions to achieve dynamic control over the assembly of colloidal particles in a magnetic medium. Expanding on this, I have experimented with controlling the orientation and direction of nonmagnetic organisms in magnetic medium, specifically Caenorhabditis elegans, using external magnetic fields. My research has provided valuable insights into the magnetic manipulation of microscopic matter, which I plan to evolve in developing tools such as cell manipulation in biomedical applications.