Despite the huge efforts and investments in biosensor research and development over several decades, implantable devices capable of providing long-term continuous monitoring of key molecular markers are far from realisation. The reasons relate to fundamental materials challenges such as biocompatibility, and practical barriers such as in-situ calibration. While the management of many chronic health conditions could benefit from scientific and technological breakthroughs that would advance our capabilities in this regard, perhaps the best known is the management of diabetes, due to the scale of the problem, its increasing scale and the huge impact on people, society and our health systems. Today, the state of the art is around 10-15 days continuous monitoring via devices that are attached to the body, and monitor glucose in interstitial fluid via a very fine filament that penetrates through the skin to access the sample fluid. Examples include the Abbott Freestyle Libre (https://www.freestylelibre.ie) and the Dexcom G6 Technologies (http://dexcom.eu/). The Abbott sensor allows the data to be transferred to a proprietary hand-held device whereas the Dexcom sensor transmits the data to more conventional platforms (mobile phones, iWatch etc.). Pressure to improve the offering from the increasingly IT literate user community is pushing these platforms towards much closer integration with mainstream IOT technologies. For example, tech-savvy parents of children with Type 1 Diabetes have set up their own technology group, and produced their own information management system called Nightscout, which has more advanced features than the industry systems. The Nightscout Project (http://www.nightscout.info/) is now driving technology advances in Continuous Glucose Monitoring (CGM), at least on the informatics side. Nightscout is an open source, DIY project that allows real time access to CGM data via a personal website, smartwatch viewers, or apps and widgets available for smartphones (Tagline “#WeAreNotWaiting”!).
These disruptive developments are also going to create a major demand for improved sensor performance, which places an increasing focus on how to dramatically extend the functional lifetime of such biosensors, and in turn demands new thinking around the fundamental materials science of long-term on-body/in-body biosensing and controlled therapeutics (in this case insulin) delivery. In this lecture, I will discuss these and related issues, and speculate on strategies for delivering longer-term sensing and control functions the inherent behaviour of materials rather than conventional approaches.