Time-Sharing Acoustic Tweezers for Parallel Manipulation of Multiple Particles

Area of Science:

• Acoustic manipulation
• Biomedical engineering
• Phased-array systems

Background:

• Holographic acoustic tweezers enable flexible particle manipulation for biomedical applications.
• Current multiparticle manipulation methods suffer from interference artifacts and lack parallelization.
• Existing techniques limit accuracy and the number of simultaneously manipulated particles.

Purpose of the Study:

• To propose a time-sharing acoustic tweezer method for enhanced multiparticle manipulation.
• To overcome limitations of interference and lack of parallel working ability in current methods.
• To advance holographic acoustic tweezers for improved accuracy and particle handling capacity.

Main Methods:

• Developed a time-sharing method using rapid switching of individual trapping beams.
• Implemented the technique on a 256-element phased-array acoustic tweezer system.
• Utilized designed ultrasonic pulse sequences to synthesize focused, twin trap, and vortex beams.

Main Results:

• Achieved pseudo-parallel manipulation of multiple particles in 3-D space at beam switching frequencies ≥10 kHz.
• Successfully trapped and assembled up to 96 polydimethylsiloxane particles into a 2-D lattice.
• Demonstrated dynamic patterning of particles into contours (e.g., sinusoidal vibration, butterfly flapping) and orbital rotation.

Conclusions:

• The time-sharing acoustic tweezer method significantly minimizes interference artifacts.
• The technique enables pseudo-parallel manipulation of a greater number of particles compared to existing methods.
• This advancement broadens the scope and potential applications of holographic acoustic tweezers in fields like cell sorting and assembly.