Woolitmus: An Approach to Minimize E-waste by Using Wool-Based Wearable Sensor for Sweat pH Detection

This study introduces "Woolitmus" a textile-based wearable sweat pH indicator developed using pyranine, also known as HPTS (8-Hydroxypyrene-1,3,6-trisulfonic acid) and naturally occurring wool as substrate. Sweat pH analysis is crucial for monitoring health conditions associated with pH imbalance. The sensor exhibits pH responsiveness under visible and UV light, offering the potential as a real-time sweat patch for pH monitoring. The interaction of pyranine with wool substrate is detailed, elucidating the mechanism behind the pH sensitivity backed up by photophysical characterizations. Stability and reversibility tests also confirm the sensor's robustness and performance. The reported sensor also can simultaneously collect and detect pH levels without the support of any additional accessories like electrodes, display, etc. It also offers sensitivity, real-time response, and non-invasive detection. But more importantly, it stands out for its biodegradability, reusability, zero e-waste, and biocompatibility of the substrate. The wool fabric-based pH sensor holds promising applications, including health monitoring and lifestyle management.