Table 1.

Physical and MPI properties of evaluated tracers

Tracer Name	Core Size (nm)	DH# (nm)	PDI	Zeta (mV)	Resolution* (mm)	LoD† (ng of Fe)
Anti-Ly6G SPIO	14.0 ± 2	78	0.097	-12.2 ± 0.6	1.26	13 ± 1
VivoTraxTM	5.4 ± 1	61	0.223	-12.7 ± 1.8	1.49	22 ± 3

*The measurements reported were carried out using an arbitrary wave relaxometer (AWR) and are converted for a 7 T/m gradient field-free-line MPI scanner operating at 20 mT and 20 kHz excitation.

^†Calculations for the limit of detection (LoD) were based on a standard curve taken in the scanner (Figure 3, FOV = 4.1 x 6.2 cm², scan time = 37 s) estimated for a pixel size of 1.4 × 1.4 mm². Standard deviation is propagated from the error in the linear fitting of the curve.

#Hydrodynamic diameter and zeta potential measured using Nano Zetasizer

(D_H: Hydrodynamic diameter; FOV: field-of-view; LoD: Limit of detection; PDI: polydispersity index).