Fig. 1: Schematic of the wet-tissue adhesion of the CPB and the potential applications.

a Wet adhesion of CP. With its original swelling ability, CP might not remove all the interfacial water. The interaction between the patch and the tissue is also affected negatively by water molecules, finally resulting in weak adhesion. b Wet adhesion of CPB. With a strong swelling capacity when adhered to wet tissues, the interfacial water can be reduced or even removed. The interaction between the patch and the tissue is not affected by water molecules and finally resulting in stronger adhesion of CPB. c Potential applications of CPB: rapid hemostasis by promoting blood coagulation and sealing the wound, physical activity biosensor by adhesion to certain sites and tumour recurrence prevention under NIR light through PTT.