Limei Tian, PhD, Texas A&M University

Wearable sensors can provide valuable information related to the health and disease states of individuals. In this seminar, I will discuss the recent progress we have made in developing wearable sensors through the design of soft, functional nanomaterials and nanocomposites. A wearable bioimpedance sensor made of conductive nanocomposites can enable cuffless and continuous blood pressure monitoring. We also developed soft, stretchable, conductive hydrogels for high-performance electronic implants. We demonstrate the in vivo application of hydrogel-based electronic devices for effective electrical stimulation and high-quality recordings in live animal models. Another example is a wearable plasmonic paper-based microfluidic system that continuously and simultaneously quantifies sweat loss, sweat rate, and metabolites in sweat. Plasmonic sensors based on surface-enhanced Raman spectroscopy (SERS) are label-free and can identify the analytes of interest via the chemical "fingerprint" information. The well-defined flow kinetics of paper microfluidic devices enable accurate quantification of sweat loss and sweat rate in real time. Reliable quantification can be achieved when the devices are under strain and at high temperatures. These wearable sensors are soft, flexible, and stretchable, providing a robust interface with the skin without inducing chemical or physical irritation.