Optoacoustics - Cleaving Cells using optoacoustics

Hyoung Won Baac and co-workers from the University of Michigan and the Wellman Center for Photomedicine in the USA report that laser-generated focused ultrasound can be used to perform high-precision, non-contact cleaving of cell clusters. They generated focused ultrasound by firing 6-ns laser pulses (wavelength, 532 nm) onto an optoacoustic lens consisting of a carbon-nanotube—polymer composite film on a concave fused-silica substrate. A 12-mm-diameter lens confined the laser-generated ultrasound to a focal region measuring 100 μm laterally and 650 μm axially, whereas a 6-mm-diameter lens provided tighter confinement of 75 μm and 400 μm, respectively. Experiments with cultured ovarian cancer cells showed that high-quality, precise ultrasonic cleaving of cell clusters was possible when the laser pulse energy exceeded 50 mJ. The findings suggest that laser-generated focused ultrasound is promising as a non-contact, non-thermal approach for performing cell and tissue surgical processes such as cleaving, patterning and harvesting.