Table 1.

Hydrodynamic sizes (HDS) and zeta potentials (Zp) of nano- and micro-sized ZnO in media containing different serum contents

Sample	Primary size (nm)	Surface area (m2/g)	HDS (nm) and Zp (eV)
			Water		DMEM		DMEM/5 % FBS		DMEM/10 % FBS
			HDS	Zp	HDS	Zp	HDS	Zp	HDS	Zp
			PDI		PDI		PDI		PDI
Nano-ZnO	50–70	7.34	279 0.18	25.9	936 0.18	−2.4	320 0.31	−7.5	329 0.17	−9.3
Micro-ZnO	<1,000	1.81	530 0.21	22.1	1107 0.35	−4.0	554 0.23	−8.2	634 0.28	−7.8