fig6

Figure 6. Flexible natural hydrogel-based pressure sensors. (A) Schematic illustrating the preparation process of a CS/CGG gel and photographs showing its application in finger bending detection. Reproduced with permission^[105]. Copyright 2021, Elsevier. (B) Schematic illustrating the fabrication strategy for making a conductive, stretchable, self-healing and anti-freezing HC-KG hydrogel and photographs showing its self-healing ability. Reproduced with permission^[108]. Copyright 2022, The Author(s), published by Frontiers in Bioengineering and Biotechnology. (C) Schematic illustrating the fabrication process, biodegradability and recyclability of a hydrogel and photographs showing its application in keyboard pressing. Reproduced with permission^[109]. Copyright 2022, American Chemical Society. CS: Chitosan; CGG: cationic guar gum; HC-KG: hyaluronic acid/chitosan-KCl/glycerol.