Holographic Microfluidic Platform That Can Make Droplets Jump
A microfluidic platform that uses a phased array to generate focused ultrasound through a hydrophobic mesh. Droplets on the mesh can be moved horizontally, merged, split, and jumped up to 10 cm — a 27-fold improvement over conventional EWOD systems. We demonstrated Suzuki-Miyaura cross-coupling and showed lower biofouling than EWOD, indicating suitability for both chemical and biological experiments.
This platform places droplets on a hydrophobic mesh that is acoustically transparent, with a 256-element phased array transducer (PAT) underneath. The PAT dynamically generates focused ultrasound that passes through the mesh to manipulate droplets up to 300 μL. Horizontal movement is achieved by steering the focal point; jumping occurs when the acoustic radiation force exceeds the sum of gravitational and adhesion forces. The system achieved jump heights up to 10 cm (27× conventional EWOD), simultaneous control of four droplets via iterative back-propagation, and droplet merging/splitting using a hydrophobic knife. We validated the platform with Suzuki-Miyaura cross-coupling reactions and confirmed lower biofouling than EWOD, demonstrating applicability to chemistry, biology, micro-robotics, and laboratory automation.
Cite this work
Yusuke Koroyasu, Thanh-Vinh Nguyen, Shun Sasaguri, Asier Marzo, Iñigo Ezcurdia, Yuuya Nagata, Tatsuya Yamamoto, Nobuhiko Nomura, Takayuki Hoshi, Yoichi Ochiai, Tatsuki Fushimi. "Microfluidic platform using focused ultrasound passing through hydrophobic meshes with jump availability", PNAS Nexus 2(7), pgad207 (2023). https://academic.oup.com/pnasnexus/article/2/7/pgad207/7197837
