Microfluidic platform using focused ultrasound passing through hydrophobic meshes with jump availability

Area of Science:

• Microfluidics
• Acoustic manipulation
• Biotechnology

Background:

• Automated droplet manipulation is crucial for chemistry, biology, medicine, and engineering.
• Electrowetting-on-dielectric (EWOD) is common but limited in droplet detachment (jumping).
• Limitations in EWOD hinder throughput and device integration for microfluidic applications.

Purpose of the Study:

• To develop a novel microfluidic system for efficient, large-scale droplet manipulation.
• To overcome the droplet jumping limitations of conventional Electrowetting-on-Dielectric (EWOD) systems.
• To demonstrate the platform's utility in chemical and biological experiments.

Main Methods:

• Utilizing focused ultrasound through a hydrophobic mesh to manipulate droplets.
• Employing a phased array to dynamically create foci for droplet control.
• Demonstrating droplet merging and splitting using a hydrophobic knife.

Main Results:

• Achieved droplet jump heights up to 10 cm, a 27-fold improvement over EWOD.
• Successfully demonstrated Suzuki-Miyaura cross-coupling, showcasing chemical experiment potential.
• Observed lower biofouling compared to EWOD, indicating suitability for biological applications.

Conclusions:

• The focused ultrasound microfluidic platform offers enhanced droplet manipulation capabilities.
• This technology significantly improves upon existing methods like EWOD for throughput and integration.
• The system holds promise for advancing micro-robotics, additive manufacturing, and laboratory automation.