Spontaneous Faradaic Charge Transfer at Bio-Graphene Interfaces

The emerging two-dimensional (2D) materials demonstrate unique transduction properties, offering a pathway to interface complex biofluids with unprecedented sensitivity and reliability. My talk will focus on an innovative self-driven Faradaic charge transfer I discovered at the interface between graphene—a carbon-based 2D material—and biofluids, at the absence of a reference electrode. The charge transfer rate, or Faradaic current, is characteristic to the electrostatic/electrochemical potential of the biofluids. I will talk about the measuring methodology, the preparation and characterization of graphene, the graphene-solution interface, and two applications of this transducing mechanism: (1) ultra-high-sensitivity interrogation of neuropeptides, small biomolecules that play center role in the nervous system, in full phosphate buffer solution and (2) structural-functional analysis of protein-nanoparticle assemblies at nanometer scale.