Understanding the Mechanisms behind Ultrasound-Microbubble Mediated Drug Delivery

Interest in microbubbles, tiny bubbles of gas that can travel safely around the circulation alongside red blood cells, has grown over recent years as they have been demonstrated as a means of targeting the delivery of cancer drugs. When microbubbles are exposed to ultrasound using a standard clinical imaging system they are forced to expand and contract causing them to push and pull on nearby tissues and generate bio-effects that can enhance drug uptake. At the same time, these microbubbles scatter sound so that the signals returning to the ultrasound scanner can be differentiated from those that come from the surrounding tissues.
Recent clinical trials have demonstrated the use of ultrasound driven microbubbles to target drug delivery in patients, but an incomplete understanding of the underpinning mechanisms has meant that delivery efficiencies have remained low. One particular challenge is the difficulty with which ultrasound driven microbubbles can be studied effectively in vivo. To overcome this, we are developing laboratory-based microvessel flow systems modelled on real tissue for controlled investigation of ultrasound driven microbubbles. Our goal is to use these systems to better understand how microbubbles can be exploited in drug delivery.
Supported by an interdisciplinary team of clinicians and biomedical engineers, the primary aim of this project is to build a comprehensive understanding of how the microvasculature influences the radial oscillation of microbubbles and the sound they scatter. As such there are several directions available to the student who embarks on this project including experimental investigation of microbubbles in artificial blood vessels and/or modelling the way in which microbubbles interact with tissues and sound. The project will be shaped by the interests of the student and supervisory team but is likely to involve some or all of the following techniques: 3D printing, microCT scanning, 3D visualisation, ultrasound experimentation on biological systems and multiphysics modelling.