Table 1. Description of the Various SPIONs in DI Water.

sample/size (nm)	functional group	TEM Size (nm)	DH(nm)a	PDIb	⟨DH⟩ (nm)c	ζ potential (mV)d	nickname
no coatinge	OH	5 ± 0.5					bare
single dextran coated	COOH	15.2 ± 1.2	39.7 ± 0.1	0.169	48.6 ± 0.6	–21.4 ± 0.4	S-negative
	plain		74.0 ± 1.0	0.209	87.6 ± 4.5	–9.1 ± 0.7	S-plain
	NH2		105.1 ± 6.2	0.248	92.0 ± 2.5	+19.3 ± 0.5	S-positive
double dextran coated	COOH	f	64.6 ± 1.3	0.24	74.2 ± 4.0	–17.8 ± 0.3	L-negative
	plain		78.6 ± 0.81	0.223	93.8 ± 5.4	–6.2 ± 0.9	L-plain
	NH2		179.5 ± 3.02	0.24	225.7 ± 11.2	+9.3 ± 1.1	L-positive

^az-Average hydrodynamic diameter extracted by cumulant analysis of the data from DLS measurements (see Figure S1).

^bPolydispersity index.

^cAverage hydrodynamic diameter determined from CONTIN size distribution (see Figure S2).

^dZeta potential measurements were determined in low ionic strength solutions to ensure electrophoretic mobility.

^eConfirmed by TEM images (see Figure 2).

^fDifficult to determine since the dextran layer is weakly scattering and there may be some agglomeration of particles during drying.