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Updated: Aug 11, 2026
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Fabrication and Operation of Acoustofluidic Devices Supporting Bulk Acoustic Standing Waves for Sheathless Focusing of Particles
Published on: March 6, 2016
A rotating ultrasonic waveguide for studying acoustic radiation forces on particles
1Department of Physics, University of Vermont, Burlington 05405.
The Journal of the Acoustical Society of America
|October 1, 1991
Summary
Researchers developed an apparatus for observing cells in a 160-kHz ultrasonic field. Biological cells and microspheres were observed to aggregate at specific intervals, explained by acoustic radiation forces.
Area of Science:
- Acoustic physics
- Biophysics
- Cellular imaging
Background:
- Acoustic fields offer precise manipulation of microscopic particles.
- Observing cellular behavior under acoustic forces requires specialized equipment.
Purpose of the Study:
- To design and validate an apparatus for studying cell behavior in a standing ultrasonic field.
- To investigate particle aggregation patterns within the acoustic field.
Main Methods:
- Developed a 160-kHz ultrasonic standing wave apparatus with a single-mode waveguide.
- Utilized a rotating chamber with aqueous metrizamide solution to contain cells.
- Recorded cell positions using photography and video microscopy with stroboscopic illumination.
Main Results:
- Observed aggregation of latex microspheres and red blood cells at half-wavelength intervals.
- Particles localized near acoustic pressure-amplitude minima.
- Particle grouping explained by a scalar-potential theory incorporating gravitational, rotational, and acoustic forces.
Conclusions:
- The developed apparatus enables precise observation of cells in ultrasonic fields.
- Acoustic radiation forces are key in organizing particles within the field.
- The findings support theoretical models of particle behavior under acoustic manipulation.
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