Smart Bandage With Wireless Strain and Temperature Sensors and Batteryless NFC Tag

This article presents a smart bandage with wireless strain and temperature sensors and a batteryless near-field communication (NFC) tag. Both sensors are based on conductive poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymer. The highly sensitive strain sensor consists of a microfluidic channel filled with PEDOT:PSS in Polydimethylsiloxane (PDMS) substrate. The strain sensor shows 3 order (similar to 1250) increase in the resistance for 10% strain and considerably high gauge factor (GF) of similar to 12 500. The sensor was tested for similar to 30% strain, which is more than typical stretching of human skin or body parts such as chest expansion during respiration. The strain sensor was also tested for different bending and the electrical resolution was similar to 150% per degree of free bending and similar to 12k% per percentage of stretching. The resistive temperature sensor, fabricated on a Polyvinyl Chloride (PVC) substrate, showed a similar to 60% decrease in resistance when the temperature changed from 25 degrees C to 85 degrees C and a sensitivity of similar to 1% per degrees C. As a proof of concept, the sensors and NFC tag were integrated on wound dressing to obtain wearable systems with smart bandage form factor. The sensors can be operated and read from distance of 25 mm with a user-friendly smartphone application developed for powering the system as well as real-time acquisition of sensors data. Finally, we demonstrate the potential use of smart bandage in healthcare applications such as assessment of wound status or respiratory diseases, such as asthma and COVID-19, where monitoring via wearable strain (e.g., respiratory volume) and temperature sensors is critical.

Automated summary

This article introduces a smart bandage equipped with wireless strain and temperature sensors and a batteryless NFC tag. The sensors, based on PEDOT:PSS polymer, show high sensitivity and large range of testing results. The smart bandage can be utilized in healthcare applications such as assessing wound status and monitoring respiratory diseases.