We propose a microfluidic system using focused ultrasound through a hydrophobic mesh to manipulate droplets on its surface, offering an alternative to Electrowetting-on-Dielectric (EWOD) systems. This method enhances droplet jump height and flexibility.
A phased array transducer dynamically creates foci, controlling droplets up to 300 µL with jump heights up to 10 cm, a 27-fold improvement over traditional methods. Droplets can be moved, merged, or split using a hydrophobic knife, demonstrating versatility for chemical and biological experiments.
The system shows lower biofouling than EWOD, making it suitable for biological applications. It handles both solid and liquid targets, expanding its use to micro-robotics, additive manufacturing, and laboratory automation. Preliminary experiments, including Suzuki-Miyaura cross-coupling, confirm the platform’s robustness and applicability. The design supports parallel manipulation of multiple droplets, enhancing throughput in automated settings.
This focused ultrasound-based microfluidic platform significantly advances droplet manipulation technology, enabling a wide range of scientific and engineering applications.
Dr. Tatsuki Fushimi 