Interfacing nanomaterials for bioelectronic applications

The integration of nanomaterials as a bridge between the biological and electronic worlds has revolutionised understanding of how to generate functional bioelectronic devices and has opened up new horizons for the future of bioelectronics. The use of nanomaterials as a versatile interface in the area of bioelectronics offers many practical solutions and has recently emerged as a highly promising route to overcome technical challenges in the control and regulation of communication between biological and electronics systems. Hence, the interfacing of nanomaterials is yielding a broad platform of functional units for bioelectronic interfaces and is beginning to have significant impact on many fields within the life sciences. In parallel with advancements in the successful combination of the fields of biology and electronics using nanotechnology in a conventional way, a new branch of switchable bioelectronics, based on signal-responsive materials and related interfaces, has begun to emerge. Switchable bioelectronics consists of functional interfaces equipped with molecular cues that are able to mimic and adapt to their natural environment and change physical and chemical properties on demand. These switchable interfaces are essential tools to develop a range of technologies to understand the function and properties of biological systems such as bio-catalysis, control of ion transfer and molecular recognition used in bioelectronics systems. This thesis focuses on both the integration of functional nanomaterials to improve electrical interfacing between biological system and electronics and also the generation of a dynamic interface having the ability to respond to real-life physical and chemical changes. The development of such a dynamic interface facilitates studies of how living systems probe and respond to their changing environment and also helps to control and modulate bio-molecular interactions in a confined space using external physical and chemical stimuli. First, the integration of various nanomaterials is described, in order to understand the effect of different surface modifications and morphologies of various materials on enzymebased electrochemical sensing of biological analytes. Then, various switchable interfaces, based on graphene-enzyme and responsive polymer that could be modulated by temperature, light and pH, were developed to control and regulate enzyme-based biomolecular reactions. Finally, a physically controlled programmable bio-interface is described by “AND” and “OR” Boolean logic operations using two different stimuli on one electrode. Together, the findings presented in this thesis contribute for the establishment of switchable and programmable bioe-