Title: Self-assembling Liposome Nano-transducers
Funder: Engineering and Physical Sciences Research Council

Abstract: Transducers are devices that can convert electrical energy into mechanical energy and vice versa. They are widely used in non-destructive testing to generate acoustic signals in test materials and to detect changes in the acoustic signal as it travels enabling material properties to be determined. The application areas for transducers in non-destructive testing are diverse and range from locating cracks in metal structures to diagnosing disease in humans. Transducers are typically made from single crystals such as quartz or ceramics. Recently it has been shown that a much wider range of materials can be used in transducers if they are miniaturised down to a nanometre scale. In fact, it has been shown that electrical energy can be converted to mechanical energy in biological membranes. Further, strategies to greatly increase the size of this effect have also been identified. These findings are very exciting as they pave the way for development of tiny transducers that could be used in the human body without posing any risk of toxicity, thus having tremendous potential for application in medicine. The work proposed in this Fellowship is centred on the development of nano-sized transducers made from phospholipids, which are the main type of fat found in membrane of biological cells. A huge area of application for the nano-transducers proposed is in medical imaging which presents a number of challenges. In practice, the nano-transducers could be used to remotely probe tissue properties and used in an imaging system to aid the diagnosis of disease. There is also a growing need for new imaging systems capable of remotely studying cells and tissues in the body to support the development of emerging therapies that use human cells to treat currently incurable conditions, such as Parkinson's disease and spinal injury, as well as chronic conditions including diabetes and heart disease. The hope is that by introducing new healthy cells into the body they will help to restore the function of injured or diseased cells. To ensure these therapies have a positive effect it is important that the location and behaviour of introduced cells are tracked once in the body. This is a challenging problem which current technologies are struggling to address. The work proposed in this Fellowship will address the above challenges. The approach that will be taken is different from other workers particularly as it will involve the development of transducers made from organic material. A major part of the proposed work will be designing and fabricating the nano-transducers. The phospholipids the nano-transducers will be composed of will be formed into bubbles called liposomes. Due to the natural link between the electrical and mechanical properties of liposomes it will be possible to use them as tiny acoustic sources. Strategies to increase the size of the acoustic signal produced will be developed based on modification of the liposome composition, shape and size. Another part of this Fellowship will be the development of a suitable imaging system using the nano-transducers that can be used to produce diagnostic images of the body. Also by controllably decorating the liposomes with specific biological molecules the nano-transducers will be able to target certain cell types enabling them to act as beacons to locate cells in the body. The final part of the work will be centred on demonstrating the capability of the new imaging system using tissue phantoms that mimic the human body. In particular, the ability to detect tumours, electrical activity in the brain and track cells used in therapy will be investigated. Overall, the success of this work will deliver a new medical imaging modality that could be implemented readily within clinical pathways at the point of care. This would have a significant impact on healthcare and enable new therapies to become available for clinical use and thus contribute to the health and wealth of society.


Research activity codes: 4.1 DISCOVERY AND PRECLINICAL TESTING OF MARKERS AND TECHNOLOGIES
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL;CANCER AND NEOPLASMS