Biocompatible MXene/Chitosan-Based Flexible Bimodal Devices for Real-Time Pulse and Respiratory Rate Monitoring

Electronic skins, often with recognition and sensing capabilities that are beyond those associated with biological skin, provide important medical information for human health. However, how to make electronic skins with both tactile and touchless perceptions for applications in real-time health monitoring is a challenge due to biological complexity. Herein, flexible bimodal e-skins are demonstrated using a lamellated MXene/chitosan film as the kernel sensing layer. These biomimetic hybrid films show excellent biocompatibility in a cytotoxicity test, indicating a reduced risk of application in the human body. The flexible devices display two modes that can detect pressure (with a limit of detection (LoD) of 3 Pa, stability >3500 times, and response time of 143 ms) and humidity (stability >20 days). The bifunctional sensor can also be used in detecting and discriminating electrophysiological signals (including voice recognition, human pulses, and finger bending) and biochemical molecules (respiratory rate). This work may lead to the application of biocomposite materials in multifunctional flexible sensing technology.