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The interaction of laser-generated tandem microbubble (maximum diameter of about $50\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$) with single (rat mammary carcinoma) cells is investigated in a $25\mathrm{\text{\ensuremath{-}}}\ensuremath{\mu}\mathrm{m}$ liquid layer. Antiphase and coupled oscillation of the tandem microbubble leads to the formation of alternating, directional microjets (with max microstreaming velocity of $10\text{ }\text{ }\mathrm{m}/\mathrm{s}$) and vortices (max vorticity of $350\text{ }000\text{ }\text{ }{\mathrm{s}}^{\ensuremath{-}1}$) in opposite directions. Localized and directional membrane poration (200 nm to $2\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ in pore size) can be produced by the tandem microbubble in an orientation and proximity-dependent manner, which is absent from a single oscillating microbubble of comparable size and at the same stand-off distance.

The interaction of a lithotripter shock wave (LSW) with laser-generated single vapor bubbles in water is investigated using high-speed photography and pressure measurement via a fiber-optic probe hydrophone. The interaction leads to nonspherical collapse of the bubble with secondary shock wave emission and microjet formation along the LSW propagation direction. The maximum pressure amplification is produced during the collapse phase of the bubble oscillation when the compressive pulse duration of the LSW matches with the forced collapse time of the bubble.