Table 1.

Various types of magnetic hydrogels and their mode of synthesis.

Hydrogel Matrix	MNPs	Concentration	Method	Ref.
Chitosan	Fe3O4	11.1–13.6 wt%	In situ	[117]
Alginate/PNIPAM	γ-Fe2O3	-	In situ	[106]
PAAm-GA	Fe3O4	8.3–14.04 wt%	In situ	[104]
Fibrin	Fe3O4	2.5 mg/mL	Blending	[60]
Dextran	CoFe2O4	2.5–15 wt%	Blending	[92]
Alginate	FePt	8 wt%	Blending	[118]
PNIPAM	CoPt	1 wt%	Blending	[91]
PAAm	CoFe2O4	2 wt%	Grafting onto	[114]
NIPAM	Fe3O4	<50%	Grafting onto	[119]
NIPAM	γ-Fe2O3	~50%	Grafting onto	[119]
CMC	CoFe2O4	1.5 wt%	Grafting onto	[113]

PAAm—polyacrylamide; PNIPAM—poly(N-isopropylacrylamide); GA—gum acacia; NIPAM—N-isopropylacrylamide; and CMC—carboxymethyl cellulose.