Theoretical evaluation to assist targeted drug delivery with ultrasound-supported sonoporation for future laser-driven studies at eli-np

Inaugural studies of medicine-supporting research foreseen to be im-plemented at the High-Power Laser Systems (HPLS) at ELI-NP will benefit substan-tially from achieving a fast and localized delivery of radiological substances. Microbub-bles driven by an ultrasonic transducer have been used successfully as delivery agents for pharmaceuticals for several decades. They can support future oncology programs facilitating high-dose rate therapies (e.g., flash therapy) at ELI-NP, since a very loca-lized and swift delivery of drugs and nanoparticles is achievable using the bubbles. We herein depict a theoretical evaluation to control the critical microbubble explosion that creates the high-pressure gradients of need for in-vitro and in-vivo sonoporation of drugs and nanoparticles based on the Rayleigh-Plesset equation. Suitable bubble sizes R0 and corresponding resonance frequencies fres are derived for which an ultrasonic -driven explosion can be achieved assuming an externally applied pressure P infinity(t) of sinusoidal nature. With R0 in the mu m and fres in the MHz regime, the crucial explo-sion times Texpl can be short (< 2 mu s) allowing the sought-after fast delivery of the pharmaceutical payload.