NSF Grant Awarded

Sung-Kwon Cho

Microfluidics have had a tremendous impact on biotechnology, biosensors, health care, and more.  Conventional microfluidics are based on a micro channel network for continuous flow streams. In contrast, digital microfluidics use droplets as the operational element, which serve as carriers and reaction chambers eliminating the need for confining physical structures. The current method most commonly used to drive these droplets is through electrowetting on dielectric (EWOD). However, EWOD often suffers from limitations such as high voltage requirement and biofouling, hampering many real applications.

Dr. Sung Kwon Cho, mechanical engineering professor, was awarded a $310,000 grant from the National Science Foundation to seek a straightforward pathway to a new digital microfluidic platform without the limitations of EWOD. The project is entitled, “Collaborative Research: Magnetically Actuated Black Silicon Ratchet Surfaces for Digital Microfluidics," and is in collaboration with Professor Seok Kim of the University of Illinois at Urbana – Champaign. 

The proposed platform exploits a purely mechanical means to drive discrete liquid droplets in a rapid, flexible, programmable, and reconfigurable manner. The key mechanism is dynamically tuning surface morphology using magnetically-actuated anti-biofouling ratchet surfaces.  As a result, droplets are essentially driven mechanically, not electrically.

This three-year collaborative research project will combine the expertise of Profs. Cho and Kim in mechanics, materials, manufacturing and microfluidics in order to achieve understanding and knowledge in the proposed system, and finally open up a new interdisciplinary research area across smart composite materials and digital microfluidics.