Investigation of materials properties and device structure on the performance of graphene-based field-effect transistors for biodetection

Graphene is a two-dimensional material that has many excellent properties that make it promising for the development of biosensors. A promising approach is to use graphene as channel in a fieldeffect transistor, where the fluid containing molecules or cells to be detected is used as a liquid gate.
We propose to apply a new method of dry transfer of graphene that is much easier to set up and to scale up than established methods and produces cleaner graphene films with improved structural properties. This will allow us to study the effect of specific surface modifications on the performance of biosensors. Surface modifications include exposure to activated nitrogen from a plasma source, or atomic-layer deposition of ultra-thin high-k dielectrics. The graphene surface will be functionalised to allow for easy covalent grafting of bioreceptors, such as a monoclonal antibody targeting a specific biomarker. We expect this work to contribute to better understanding of some of the current limitations in graphene-based biosensors, identify possible solutions and provide a basis for producing simple ready-to-use sensors for sensitive, specific and reproducible detection of cancer cells in blood or plasma. By extrapolation, the development of such technologies could be easily extended to other biosensing application related to public health (diagnostic tools for infectious diseases, auto-immune and metabolic diseases etc…) or even biotechnologies (detection of food contaminants, water pollutants etc…).