Flexible Wearable for Addressing Health Disparities

This work develops new electrochemical wearable sensors and systems. We developed these sensors from laser-induced carbon. Laser-induced graphene (LIG) has become a focal point of recent research due to its promising applications in sensing devices. This material is produced by exposing carbon-rich polymers, especially polyimide, to a laser beam. The laser irradiation induces localized photothermal reactions, transforming SP3 carbon atom hybridization into a three-dimensional, graphitic-like structure. This method, which is maskless, scalable, straightforward, reproducible, cost-effective, and rapid, generates high-quality graphene layers. These layers possess remarkable flexibility, electrical conductivity, and electrocatalytic properties, offering advantages over traditional methods such as wet chemistry, ink-jet printing, and chemical vapor deposition, which are often more complex, time-consuming, and costly. In this work, we investigate the surface modification and properties of graphene to achieve a stable interfacial potential with a lipophilic sensing membrane in a potentiometric readout mode. We specifically examine how the material's surface topography and hydrophilicity affect the long-term and short-term properties of wearable sensors and explore use of redox mediators to address the sensor calibration drifts. Robust sensors are achieved through this engineering of the LIG surface. We demonstrate application of these sensors for development of wearable sensors tailored to address unmet needs in women’s health.