Preparation of Poly(γ-glutamic acid) Hydrogels with Ionic Liquids and Their Application as a Strain Sensor

In recent years, the increasing interest in health and fitness has led to enhanced research into wearable devices capable of monitoring various human body motions. Strain sensors, which are integrated into wearable devices, provide the capability to monitor bodily movements in real time by detecting the strain applied to the material due to changes in motion, heart rate, and blood pressure. This study investigates a polymer hydrogel composed of biocompatible poly(γ-glutamic acid) and an ionic liquid, developed as a strain sensor. The hydrogel exhibits notable flexibility, maintaining its functionality even when subjected to bending or stretching. Furthermore, it contains a substantial amount of water, facil-itates ionic movement, and can emulate the softness and flexibility of human skin, thus demonstrating its potential for seamless integration into daily life.