A Digital Acoustofluidic Pump Powered by Localized Fluid-Substrate Interactions.

Area of Science:

• Fluid dynamics
• Acoustics
• Microfluidics

Background:

• Precise liquid transport in microfluidic systems is crucial for applications like clinical diagnostics.
• Existing methods face challenges in handling small volumes and diverse liquid types accurately.

Purpose of the Study:

• To present a reliable digital pump for precise nanoliter-scale liquid transportation.
• To demonstrate the pump's capability in handling various liquid viscosities and enabling digital flow control.

Main Methods:

• Utilizing acoustic streaming induced by localized fluid-substrate interactions.
• Employing a C-shaped interdigital transducer (IDT) to generate acoustic streaming within a microchannel.
• Achieving digital regulation of flow with a rapid response time.

Main Results:

• Generated stable, unidirectional flow at approximately nanoliter per second rates.
• Demonstrated precise digital regulation with response times around one second.
• Successfully handled both aqueous solutions and high-viscosity liquids like human blood.

Conclusions:

• The developed acoustofluidic pump offers low cost, programmability, and high precision for small-volume liquid control.
• This technology has significant potential for point-of-care diagnostics, precise drug delivery, and biomedical research.
• The pump overcomes key challenges in microfluidic liquid transportation.