Abstract

Tissue functions at a cellular level by exchange of molecules between cells and blood or between the cells themselves. This produces patterns of molecular change that are diagnostic of cellular processes. The origin of these molecular changes can be physiological (exhaustion) or pathological (injury, renal failure, cancer). Our monitoring technologies have now developed to a point where we can aspire to do more than single point-of-care measurement, to measure from patients in real-time. The has the great benefit that it is then possible to understand the evolution of disease, the effectiveness of treatments, and ultimately to guide treatment. In this presentation I will describe the development of biosensor-based microfluidic devices connected to wireless electronics for monitoring of the injured human brain in the intensive care unit, transplant organs in transit, and athlete monitoring. Tissue sampling is via an integrated microfluidic device, a microdialysis probe. Molecular biomarkers are measured using microscale integrated amperometric biosensors and solid-contact ion-selective electrodes (ISE) for tissue ionic balance. For detailed patterns of ionic responses we have developed high density Field Effect Transistor (FET) array which function as ISEs within the flow stream. We have also developed multiphase flow microfluidic systems for highest time resolution. The presentation with describe the design and optimization challenges and include clinical examples from our recent work.