Acoustic pressure reporting and mapping using antibubbles

Antibubbles are a novel carrier for precise, ultrasound-triggered delivery of fluid or nanoparticulate payloads. These structures combine the high acoustic contrast and strong acoustic response of conventional microbubbles with a significantly higher payload capacity thanks to their large fluid core. The release characteristics of antibubbles can be precisely tuned during fabrication to enable release across a range of pressures spanning a few kPa to several hundred kPa. Moreover, antibubbles can release these payloads either all at once, or incrementally across multiple ultrasonic pulses. This talk will illustrate how such characteristics make antibubbles unique reporters for ultrasonic pressure, and how the fabrication and design determine the antibubble’s response. We use high-speed microscopy to highlight the relationship between the antibubble and its released payload. Finally, it will be shown that by properly tailoring the payload, formulation, and supporting matrix, spatial maps of complex acoustic pressure fields can be produced and read out optically, providing real-time diagnostic information about spatially structured ultrasonic fields.