Table 1.

Comparisons of different adhesive mechanisms for hydrogels.

Hydrogel	Adhesion type	Features	Adhesion strength (kPa)	Ref.
QCS/PAM	PDA	Strong and repeatable tissue adhesion, good tensile property (1154%), antibacterial ability	27.2	[84]
PAA/CS	TA	Skin affinity, highly stretchable, self-recovery capacity, antifatigue property	20	[79]
PVA/Graphene	PDA	Good tensile strength (1.174 ​MPa), excellent elongation (331%), recyclable, antibacterial ability	1.735	[81]
CS/Gelatin	DA	Sustained drug release, anti-infection capacity, antibacterial ability	>20	[86]
OHA	DA	Tissue adhesion, self-healing property	15.2	[49]
Gelatin	DA	No cytotoxicity, tunability	43	[34]
Gelatin	TA	Self-healing property	36	[78]
PAA	TA	Repeatable, conductive, self-solidified, antibacterial ability	25	[87]
PEG	Amidation	Antibacterial ability, controllable gelation time	20	[27]
Gelatin	Amidation	Antibacterial ability, biocompatibility	4.8–56	[88]
TPU/PAAm	Hydrogen bonding	Self-healing property, compliance	9.46	[89]
PLS/CS/RSF	Imine linkage	Biodegradability, biocompatibility, low immunogenicity	70	[90]
NB/CMC/CMC	Imine linkage	Biocompatibility, biodegradability, antibacterial ability	56.85–97.65	[43]