Table 1.

Summary iron quantification with FFC-NMR, imaging flow cytometry and a conventional colorimetric assay; SSC = side-scattered light; *p < 0.05 vs. control; **p < 0.001 vs. control. ‘Mean R1′ was obtained by averaging R1 values at all tested evolution fields for each USPIO exposure concentration (the average of all the R1 values on the dispersion curve for each tested exposure). The points on each dispersion curve were in themselves plotted using an average of 3 scans (each evolution field has 3 R1 values).

USPIO concentration (μg/ml medium)	FFC-NMR non-fixed Mean R1 of 1 × 106 cell suspension (s−1)	FFC-NMR fixed Mean R1 of 1 × 106 cell suspension (s−1)	Imaging cytometry non-fixed		Imaging cytometry fixed	Colorimetric reference iron assay Iron concentration of non-fixed 1 × 106 cell culture (ng/μg protein)
			Mean USPIO area/cell area	Geometric mean SSC intensity	Mean USPIO area/cell area
0 (control)	0.308 ± 0.014	0.439 ± 0.075	0.034 ± 0.001	26,860	0.044 ± 0.0004	0.115 ± 0.118
5	0.356 ± 0.013**	0.719 ± 0.026**	0.036 ± 0.001	32815**	0.046 ± 0.0003**	1.121 ± 0.045*
10	0.432 ± 0.016**	1.153 ± 0.024**	0.037 ± 0.001*	39573**	0.055 ± 0.0003**	2.074 ± 0.084*
40	0.706 ± 0.021**	2.348 ± 0.017**	0.069 ± 0.001**	69285**	0.072 ± 0.0003**	5.496 ± 0.134*
80	1.174 ± 0.031**	3.502 ± 0.147**	0.085 ± 0.001**	80967**	0.077 ± 0.0004**	8.421 ± 0.269*
100	1.239 ± 0.033**	5.174 ± 0.168**	0.090 ± 0.001**	82693**	0.078 ± 0.0003**	9.771 ± 0.100*
200	1.599 ± 0.041**	7.755 ± 0.257**	0.097 ± 0.001**	86373**	0.151 ± 0.0007**	12.398 ± 0.233*