A High‐Stability Hydrogel Sensor for Pulse Monitoring

Recent advances in flexible sensor technology have driven the widespread adoption of smart wearable devices. Pulse sensors, which monitor heartbeats, provide essential information about human health and serve as vital tools in personal health management, disease prevention, and medical diagnosis. However, developing sensor materials with high reproducibility for the precise detection of weak pulse signals remains challenging. In this work, a pulse‐sensing composite conductive hydrogel (PCP) was fabricated via a five‐cycle freeze–thaw method for application in traditional Chinese medicine (TCM) pulse diagnosis. The hydrogel was composed of polyvinyl alcohol (PVA), chitosan quaternary ammonium salt (CHACC), and PEDOT:PSS in an optimized mass ratio of PVA:CHACC = 7:3. It exhibits outstanding tensile strain (567%), a broad sensing range (0%–250%), fast response (0.7 s), excellent repeatability (over 1000 cycles), and high conductivity (1.5 S/m). These properties allow precise monitoring of motion signals from different body regions with sustained stability. Furthermore, the hydrogel showed antibacterial activity against Staphylococcus aureus with an inhibition zone diameter of 18.2 ± 0.5 mm, indicating enhanced biosafety. An integrated three‐channel wristband sensor based on this hydrogel was also developed, enabling real‐time and accurate detection of human pulse signals. This system provides a promising platform for digitized pulse diagnosis in wearable health monitoring.