Research Fellows Directory
Professor Duncan Graham
University of Strathclyde
Silver or gold nanoparticles offer significant opportunities in the field of medical imaging and diagnostics due to their unique optical and physical properties. This research aims to harness these properties for both diagnostic and therapeutic benefits. The science proposed has a fundamental research focus and is highly applied nature in the longer term. The basic aim is to create new nanoparticles (spheres of metal with different diameters of less than 100 nm) that can be functionalised to carry specific molecules which relate to either identification of particular disease markers or carry drugs which improve the efficacy of that drug due to different properties once mounted on a nanoparticle.
Metallic nanoparticles have been around for centuries and are commonly found in stained glass windows due to their optical brightness but they also have significant benefits when used as a diagnostic tool. Adding a specific biomolecule such as a DNA sequence or antibody to the surface of these nanoparticles can allow them to interact with their partner biological molecular (e.g. DNA or antigen) to provide a response which can be measured using differences in light. When light is allowed to interact with these nanoparticles, a particular signature of the light which is returned from the nanoparticles, can be measured. This signature relates to the molecular structure of the species bound to the nanoparticles and is sensitive enough to allow detection of one molecule. The research undertaken investigates how the light which comes back from these nanoparticles can be made informative and relates to the interacting species and hence inform on particular disease markers. Disease markers are molecules which could be small molecules or large biomolecules which are indicative of the progression of a disease. For instance, infectious disease produces molecules such as antigens or foreign DNA sequences which should not be present in the host. Therefore, detection of these foreign molecules at early stages of the onset of the disease allows more effective treatment. Normally, a disease has to manifest itself to a particular level of infection before it can be detected by conventional techniques such as the polymerase chain reaction or immunoassays. In addition, the length of time it takes for a result to be obtained from taking the sample can be anything up to several weeks. The use of appropriately functionalised nanoparticles offers excellent opportunities for the creation of new ultra sensitive and rapid methods for the detection of disease. In the last year the focus has been on the use of nanoparticle assemblies for detection of DNA relating to fungal infections and a significant new program of research on biomarkers for cardiovascular disease has just started. Use of functionalised nanoparticles as imaging agents for cells and tissue continues to show promise and will be combined with the molecular diagnostic capability shown in vitro for future studies.
Interests and expertise (Subject groups)