Table 1.

Physicochemical characterization of nanoparticles

Measure	Co3O4	CoO
Primary size (nm)	20.2 ± 0.4	65.4 ± 2.8
Hydrodynamic size (nm)
in DW	93.4 ± 1.8	380.3 ± 14.4
in PBS	468.9 ± 24.3	449.1 ± 8.9
Polydispersity
in DW	0.18 ± 0.03	0.72 ± 0.02
in PBS	0.26 ± 0.02	0.69 ± 0.05
Surface area (m2/g)	35.8	8.5
Zeta potential (mV)
in DW	39.53 ± 0.72	6.99 ± 1.18
in PBS (pH 7.4)	−26.40 ± 0.90	−21.80 ± 0.45
Solubility (%) in ALF	11.46	92.65
Solubility (%) in PBS	0.02	4.12
Endotoxin	ND	ND

Data were presented as mean ± SEM

ND, not detected