Illustration of a particle (red sphere) trapped by the 3D trapping node created by two superimposed, orthogonal (at right angles), standing surface acoustic waves and induced acoustic streaming (credit: Carnegie Mellon University)
A team of researchers at three universities has developed a way to use “acoustic tweezers” (which use ultrasonic surface acoustic waves, or SAWs, to trap and manipulate micrometer-scale particles and biological cells — see “Acoustic tweezers manipulate cellular-scale objects with ultrasound “) to non-invasively pick up and move single cells in three mutually orthogonal axes of motion (three dimensions).
The new 3D acoustic tweezers can pick up single cells or entire cell assemblies and deliver them to desired locations to create 2D and 3D cell patterns, or print the cells into complex shapes — a promising new method for “3D bioprinting” in biological tissues, the researchers say in an open-access paper in the Proceedings of the National Academy of Sciences (PNAS).