An invention may turn one of the most widely used materials for biomedical applications into wearable devices to help monitor heart health. [Holistically Engineered Polymer–Polymer and Polymer–Ion Interactions in Biocompatible Polyvinyl Alcohol Blends for High‐Performance Triboelectric Devices in Self‐Powered Wearable Cardiovascular Monitorings](https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202002878)