Table 1.

Physicochemical characterization of nanoparticles.

	Uncoated ZnO	Silica-coated ZnO	Uncoated ZnO with corona	Silica-coated ZnO with corona
SSA (m2/g)*	41.0	55.0	N.A.	N.A.
Dxrd (nm)*	29.0	28.0	N.A.	N.A.
DH (nm)	322 ± 1	460 ± 7	2039 ± 163	2119 ± 64
ζ(mv)	30.1 ± 0.7	−15.4 ± 1.3	−27.2 ± 2.0	−19.6 ± 2.8

SSA – specific surface area

D_xrd – primary particle size based on X-ray diffraction

D_H – hydrodynamic diameter

ζ - zeta potential

N.A. – not applicable.

^*SSA and D_xrd measurement for uncoated and silica-coated ZnO NPs were previously reported (Sotiriou et al., 2014)