Data-driven design of organic mixed conductors

Electronic devices have been transforming healthcare since the invention of the first electrocardiographs and pacemakers. Organic bioelectronic devices are cutting-edge healthcare technologies that translate biological signals generated by ions into electrical current, bridging the gap between biology and electronics. Organic bioelectronic devices have the potential to revolutionise medicine by treating conditions that traditional therapies cannot cure, and without the side effect associated with drugs. They are made of flexible materials which can be tailored to match the properties of different organs/tissues, limiting the body’s inflammatory response; this makes them ideal as implants for nerve regeneration after spinal cord injuries. They are also much more sensitive than silicon-based devices, allowing researchers to resolve signals from individual neurons – thus helping track down the source of seizures in epileptic patients. Other promising applications include sensing and diagnostics, from wearable glucose sensors for diabetes to ingestible devices to replace invasive exams such as gastroscopies or colonoscopies. Despite this tremendous potential, designing new materials for bioelectronics is extremely challenging, and the state of the art is limited to a handful of successfully tested materials. Bioelectronic devices behave like sponges or gels, absorbing and releasing ions and water. Thus, suitable “mixed conducting” materials must be both hydrophobic (to transport electronic charges) and hydrophilic (to accommodate water/ions). We understand how electrons and ions move, separately, in different materials, but designing a single material with the right balance between these two contrasting properties is very difficult. Even small changes to the chemical structure of mixed conductors can drastically affect the ionic/electronic conductivity. We do not yet have general rules that can help us predict how a certain material will perform. A systematic exploration of the chemical space is vital to address the various requirements for each application. However, bioelectronics currently lacks datasets to enable large-scale materials discovery. This project addresses these challenges using large-scale molecular simulations and computational tools borrowed from other fields, such as drug discovery, that have not yet been applied to bioelectronics. We will design thousands of potential new materials, then use “computational microscope” techniques to predict how they absorb water and ions, and select those with the best ionic/electronic conducting behaviour. Experimental Project Partners will synthesise the most promising candidate materials, validating our predictions and helping refine our predictive models. By collecting a high volume of data on hundreds of new materials, we will gain a better understanding of the fundamental laws governing mixed transport. Our computational exploration will not only benefit our experimental Partners, but the wider bioelectronic community. We will share our results, tools and data, enabling other researchers to build on our work and accelerating innovation in bioelectronics and related fields (drug delivery, batteries, artificial neural networks). Our project is ambitious, but our team has the right skillset: we combine unique expertise in bioelectronics, computational modelling (predicting the properties of new materials), chemical synthesis (making and testing new mixed conductors), and software development (solving technical problems to advance scientific discovery). In the future, organic bioelectronics may become the new standard for treatments and diagnostics of a wide range of medical conditions. By better understanding the structure and properties of mixed conductors, this project will bridge a fundamental knowledge gap and boost the design of improved bioelectronic devices.