Figure 1.

Bioinspired hydrogel materials and their applications in recently developed wearable devices. They can be divided into the ionic conductive hydrogel, conductive polymer hydrogel, and conductive micro/nanocomposite hydrogel. Current hydrogel wearable devices are mainly “electronic skin”, reproduced with permissions from refs 4 and 5. Copyright 2020 Royal Society of Chemistry and copyright 2020 Wiley, respectively; and “microneedle”, reproduced with permissions from refs 6 and 7. Copyright 2019 Wiley, respectively, and “contact lens”, reproduced with permission from refs 8 and 9. Copyright 2021 Elsevier and copyright 2020 American Society for Pharmacology and Experimental Therapuetics, respectively.