Table 2.

Main models, advantages, and disadvantages of HA hydrogel [50].

HA hydrogel models	Bond interactions	Advantage	Disadvantage
Physical or reversible hydrogel	H-bonding	Soft gel	Not stable
	Van der Waals interactions	Nontoxic	Low mechanical resistance
	Hydrophobic forces		Different pure size
	Molecular entanglements
Chemical or permanent hydrogel	Covalent bonds	Soft gel	Could be toxic
		Controlled pore size