Fig. 1

Characterization and in vitro hybrid enzymatic mimetic activity of CeONZs. A Appearance of CeONZs powder. B XRD pattern of the CeONZs showed four characteristic diffraction peaks. C TEM images of CeONZs displayed consistent shape and size with a lattice structure (Scale bar = 5 nm). D Magnified TEM image of a single particle where a red line was plotted to calculate the d-spacing of (111) plane (Scale bar = 2 nm). E SEM image of small-sized CeONZs (Scale bar = 100 nm). F XPS spectrum indicated the presence of Ce³⁺ and Ce⁴⁺ bivalent states in CeONZs. G FTIR spectrum of CeONZs showed the surface capping by ethylene glycol. H Hydrodynamic size of CeONZs measured by DLS in ddH₂O (about 228 nm). I Zeta potential of CeONZs in ddH₂O (+ 36.2 mV). J Visual CAT- and SOD-mimetic enzyme activities of CeONZs after H₂O₂ addition and boiling for 15 min. K Colorimetric SOD-mimetic enzyme activity of different concentrations of CeONZs. Data are presented as mean ± SEM