Cavitation inception on biological cells

Cavitation is well established in medical therapy, e.g. for renal stones lithotripsy, removal of blood clots, HIFU, histotripsy, embolotherapy, and more recently even for targeted cell drug delivery. The interaction of cavitation with cells, the extra-cellular matrix, and tissue is well understood and mostly caused by mechanical forces. Yet, the origin of cavitation in medical therapy is an open problem, which is addressed in this presentation.

We have designed an experiment to study the interaction of individual cells with shock and rarefaction waves microscopically. The waves are generated through a laser-induced plasma in a micrometer thick and liquid-filled gap composed of two glass slides. The gap also contains the cells. The plasma launches a high amplitude rarefaction wave followed by a shock wave due to faster wave propagation in the glass. We utilize high-speed imaging for visualization of cavitation inception on two different eukaryotic cell lines. We find predominant cavitation nucleation on the lipid bilayer and compare this scenario with the nucleation of cavitation on giant lipid vesicles