Biology uses reduction-oxidation (redox) reactions (reactions in which a reactant in a chemical reaction gains one or more electrons) to perform important functions: energy harvesting (respiration); biosynthesis (production of a chemical compound by a living organism); defense (inflammation); and communication (redox signaling). The investigators' unique insight is that the electrical features of this redox modality--the "flow" of electrons through redox reactions--is accessible through simple electrode-based instrumentation and that applications can be developed to both observe (sense) and intervene-in (actuate) biological systems. The research team plans to develop the fundamental theories and methods needed to build and characterize a materials-interface for the "redox-based translation" between the molecular language of biology and the electrical language of modern devices. The investigators envision that redox-linked bioelectronics will enable a new generation of bioelectronic applications for medicine (e.g., for point-of-care diagnosis), commerce (e.g., wearable electronics), and the environment (e.g., remote sensing). Through this project the investigators will continue nurturing their research ecosystem that: (i) crosses disciplines and spans the globe; (ii) generates new theories/methods and iteratively accelerates their testing through diverse collaborations with problem-focused researchers; (iii) leverages contributions from basic and applied scientists/engineers from government, academia and the private sector; and (iv) disseminates these advances through individualized training (e.g., of graduate, undergraduate and high school researchers as well as teacher-training summer programs), integration into undergraduate curricula (at the community college, undergraduate college and minority serving university levels), and transfer to the public (by hosting specialized technical conferences and generating videos for the general public).
The long-term vision of this project is to fuse the orthogonal information processing capabilities of biology and electronics through redox-linked bioelectronics. The focus of this project is on a subset of problems involving communication through a redox-signaling modality that is used by the immune system for inflammation and wound healing. The Research Plan is organized under three objectives. The FIRST objective is "Electro-bio-fabrication to Build the Bio-Device Interface." Hydrogel-based interfaces (i.e., films) will be created using an iterative approach that "teaches" how electrical signals can guide the emergence of complex structure from self-assembling polysaccharides (chitosans). The investigators propose to optimize the chitosan-based fabrication by controlling the local electrical field, salt concentration and electrostatic crosslinking. Advanced computational simulation and machine-learning will be implemented to gain mechanistic understanding of the fabrication process. The ability to controllably organize and reconfigure bio-based soft matter will enable the creation of adaptive, compatible, high-performance and sustainable materials systems for a range of life science applications. The SECOND Objective is "Electrochemistry to Discover and Characterize Materials." Novel electrochemical methods will be used for the automated, adaptive and ultimately autonomous discovery and characterization of materials that can control the transport (i.e., flow) of electrons and molecules. The simplicity, speed and data-richness of redox-based electrochemical measurements facilitates coupling to machine learning, and these capabilities could shift the paradigm for "chemical information" from a chemistry perspective (composition and concentration) to an information theory perspective. Such a paradigm shift could both improve reliability and facilitate translation for point-of-care and wearable electronics. The THIRD Objective is "Redox to Link Bio-electronic Communication." Test bed demonstrations will integrate activities across objectives. Synthetic biology constructs will be generated as observable "information processors" for a microfluidic gut-on-a-chip model of the microbiome. The immediate goal is to demonstrate that these multilayer films allow a bi-directional "flow" of molecularly-based redox information. These test bed studies are expected to provide the technical knowledge needed to build devices (e.g., capsular endoscopy systems) that can survey a redox environment and contribute to sculpting this environment.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
