2021/03/16 by Craig S. Carlson, Ryunosuke Matsumoto, Koji Fushino +3 · 1 citation
Materials Science · Engineering · #Ultrasound and Cavitation Phenomena #Ultrasound and Hyperthermia Applications #Pickering emulsions and particle stabilization
paper · pdf · doi:10.35848/1347-4065/abef0f
openalex publication_date 2021/03/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Abstract Most ultrasound contrast agents used in ultrasonic imaging comprise shell-encapsulated microbubbles, whose ingredients have been associated with adverse bioeffects. In this study, we investigated the nucleation behaviour of carbon black dispersion, whose hydrophobic nanoparticles are used intradermally. For a hypothetical, perfectly spherical carbon black particle surrounded by a perfectly spherical gaseous void, we derived a theoretical nucleation threshold of only 1.3× the resting radius. Carbon black particles and aggregates thereof were investigated using high-speed photography during 1.0 MHz sonication. The nucleation threshold found experimentally is lower than the Blake cavitation threshold of 2.0× the resting radius of free, unencapsulated microbubbles. Therefore, carbon black dispersion may be a promising ultrasound contrast agent.