Acoustic trapping based on surface displacement of resonance modes

Area of Science:

• Acoustic manipulation
• Biophysics
• Microfluidics

Background:

• Current acoustic trapping systems require high power or complex setups, limiting flexibility and increasing costs.
• Existing methods often rely on cavity modes or intricate phase control arrangements.
• There is a need for simpler, more cost-effective, and flexible acoustic trapping solutions.

Purpose of the Study:

• To present a novel concept for acoustic trapping of particles and cells.
• To enable dynamically defined trapping patterns in a simple and inexpensive setup.
• To overcome the limitations of existing high-power or inflexible acoustic trapping technologies.

Main Methods:

• Utilized a modified piezoelectric transducer in direct contact with the liquid sample.
• Developed a physical model to explain the acoustic force potential and trapping mechanisms.
• Demonstrated dynamic patterning of particles and biological cells.

Main Results:

• The modified transducer induces axial trapping supplemented by surface displacement-dependent lateral trapping.
• A horizontal array of frequency-dependent potential minima was achieved for lateral trapping.
• The system enables dynamic arraying of levitated trapping sites at low power.

Conclusions:

• The developed acoustic trapping system is inexpensive, low-power, and easily assembled.
• It offers dynamic operation and dexterous trapping capabilities for particles and cells.
• Potential applications include cell-based sample preparation and cell culture.