Nucleating and sustaining acoustic cavitation for biomedical applications

Abstract

Wes Nyborg was a pioneer in the field of biomedical ultrasound. In particular, Nyborg conducted extensive studies that provided insight into how bubbles oscillating in liquids generated forces that could alter the anatomy and/or physiology of cells. While these studies demonstrated that acoustic cavitation is instrumental in a variety of bioeffects, nucleating and sustaining acoustic cavitation in a controlled manner has proven to be a challenge, particularly in vivo. Studies have shown that these challenges can be addressed with the use of novel materials, particles, and/or acoustic pulsing schemes. In particular, pH-sensitive polymers with varying hydrophobicity have been used to sustain cavitation/cell interactions and vaporizable perfluorocarbon nanoemulsions have been used to reduce the pressure threshold for cavitation nucleation. The impact of these materials and particles on cavitation-mediated bioeffects will be discussed.