Table 3.

Main characteristics of iron oxide-based negative CAs. Note, the reported r₂ and r₂/r₁ values were expressed per mM of iron atoms.

	Composition	Size nm	r2 mM−1.s−1	r2/r1	T °C	B0 T	Ref.
SPIO	Fe2O3 NPs in Dextran	50–100	160	4.0	37	0.47	[72]
	Fe2O3 NPs in carboxylate Dextran	30–50	190	7.9	37	0.47
USPIO	Fe2O3 NPs in Dextran	17–20	53	2.2	37	0.47
MION	Fe2O3 NPs in Dextran	18–24	35	2.2	37	0.47