Investigation of Sweat Biomarkers for Real-time Reporting of Infection and Inflammation Using Wearable Sweat Sensor

Inflammatory biomarkers are modulated due to an infection or inflammatory trigger. Cytokines are inflammatory biomarkers that orchestrate the manifestation and progression of an infection/inflammatory event. Hence, non-invasive, real-time monitoring of cytokines can be pivotal in assessing the progression of infection/inflammatory event. However, real-time monitoring of biomarkers is not feasible with the current technology as most of them rely on blood-based detection. Continuous monitoring of host immune markers in sweat can aid in realtime monitoring of the immune status. This dissertation demonstrates a wearable SWEATSENSER device that can track the levels of immune cytokine markers in real-time from passively expressed sweat. The developed device is of a watch form-factor that can be worn on the arm to reliably track the biomarker response from low volumes of sweat (~1 μL) and the biomarker levels can be monitored in real-time. The developed SWEATSENSER device was validated for reliably reporting the levels of several cytokines and chemokines. Additionally, this work presents a thorough validation on the presence of certain critical infection and inflammatory markers such as interferon-inducible protein (IP-10) and tumor necrosis factor- related apoptosis-inducing ligand (TRAIL), C-reactive protein that make it feasible for using sweat as a biofluid for actively monitoring the health status. Additionally, human subject clinical studies demonstrate the feasibility of non-invasively tracking infections such as influenza from sweat. Such a wearable device can offer significant strides in improving prognosis and provide personalized therapeutic treatment for several inflammatory/infectious diseases.