Table 4.

NO-releasing hydrogels based on covalently bound NO donors.

Hydrogel	NO Donor	NO Release Features	Reference
Poly(vinyl alcohol)	N-Diazeniumdiolate	~48 h	[123]
Poly(vinyl alcohol)	RSNO	Photochemical release	[39]
Pluronic F-127	RSNO		[124]
Pluronic F-127 and branched PEI	N-Diazeniumdiolate	Burst release in first hours, sustained up to 50 h	[77,125]
Chitosan	N-Diazeniumdiolate	Enzymatic deprotection by glycosidase	[126,127]
NapFFGEE peptide	N-Diazeniumdiolate	Enzymatic deprotection by glutathione/ glutathione S-transferase	[96]
Naphthalene-terminated FFGGG peptide	N-Diazeniumdiolate	Enzymatic deprotection	[94]
Fmoc-Pexiganan and Pexiganan	N-Diazeniumdiolate	~400 h	[128]
Gelatin	SNAP	Burst release in first 2 h, sustained up to 72 h	[95]
Chitosan and hyaluronic acid	SNAC	Burst release in first 2 h, sustained up to 48 h	[41]
Chitosan	N-Diazeniumdiolate	~48 h Enzymatic deprotection	[65]
Fibrin	SNAP	Light exposure	[92]
Laponite-poly(pentaethylenehexamine) composite	N-diazeniumdiolate	Burst release	[129]
Alginate modified with DETA	N-Diazeniumdiolate	~4 days	[80]
PEG	S-nitrocysteine	~24 h	[130]
Poly(caprolactone)/Poly(sulfhydrylated polyester)	RSNO		[64]
Nap-FFKEGG	N-Diazeniumdiolate	No burst release	[131]
Alginate and branched PEI	N-Diazeniumdiolate	Addition of Cu (II) increases NO release rate	[27]
Chitosan, PEG, and glucose	Nitrite SNAC		[132]
Poly(ε-lysine)	N-Diazeniumdiolate	~15 h	[76]
Poly(2-hydroxyethyl methacrylate)	Ruthenium nitrosyl	Photochemical release	[122]