Sonicated Coated Microbubbles
Coated microbubbles are extensively used in medical sonography to enhance ultrasound contrast. Recently, such ultrasound contrast agents have been promoted as potential drug carriers for ultrasound-guided targeted drug administration.
Despite the progress achieved, a full understanding of the dynamics of ultrasound contrast agents is still lacking which hinders the development of new diagnostic and therapeutic applications. Our experimental studies are aimed at a detailed characterisation of their non-linear oscillation, translational, and clustering dynamics. The microbubble dynamics, driven by MHz-frequency ultrasound, is recorded through ultra-high-speed videomicroscopy imaging. However, experiments with bubbles suffer from interference with walls because of buoyancy. In this regard, we use optical tweezers to precisely control the positioning of individual microbubbles in the three-dimensional space. The results are compared with theoretical predictions and serve to gain further insights on the role of the encapsulating shell in the overall microbubble dynamics.