GRK 2948 Colloquium with Dr. Ines Weber

Chemical sensors hold promise for personalized health monitoring in minimally invasive applications such as breath analysis and interstitial skin fluid (ISF) or sweat monitoring. Despite their potential, these sensors are not yet established in daily practice, mainly due to their limited selectivity, sensitivity, and stability. Tailoring materials at the nanoscale offers a promising solution to enhance chemical sensing and overcome these challenges. For example, combining highly sensitive chemo-resistive sensors with nanoparticle filters enables the selective detection of breath acetone and limonene. This facilitates the real-time monitoring of metabolic processes such as exercise, cardio-respiratory fitness, diabetes and intermittent fasting diets by measuring breath acetone. Additionally, measuring breath limonene can assist in diagnosing liver disease. While breath analysis holds tremendous potential, it is limited to volatiles. To detect non-volatile biomarkers such as neurotransmitters and hormones, sensors capable of operating in ISF or sweat are needed. This requires not only high sensitivity, selectivity, and stability, but also high flexibility or stretchability to seamlessly integrate with soft skin. Such performance can be achieved through high surface area carbon-based sensors embedded in stretchable polymers. Doping these sensor materials with single-atom metal sites and applying selective coatings results in novel sensing capabilities with high potential for interstitial skin fluid or sweat monitoring. In the future, measuring both breath and ISF/sweat parameters may provide a unique advantage over a single technique, as it allows for the monitoring of a multitude of biomarkers and their interplay, yielding a comprehensive understanding of biological processes and health.