OH-Free Catalytic Decomposition of H 2 O 2 by GdVO 4 :Eu 3+ Nanoparticles

H 2 O 2 is known to be one of the initiators provoking biomolecules (lipids and proteins) oxidation and cell mutation and death. In this context, molecules, which can react with H 2 O 2 without generating free radicals such as hydroxyl radicals (·OH), are of special interest as effective preventive antioxidants. In the present study, we report on GdVO 4 :Eu 3+ nanoparticles (NPs) as prospective preventive nanozymes. Synthesized GdVO 4 :Eu 3+ NPs were characterized by TEM, HR-TEM, XRD, SAXS, and XPS methods. It has been revealed that in water solutions GdVO 4 :Eu 3+ NPs are in the form of individual crystalline spheroids with l = 12.1 ± 1.23 nm and d = 5.76 ± 0.68 nm. Using the optical spectroscopy technique, the possibility for Fenton- and CAT-like reactions in water solutions containing GdVO 4 :Eu 3+ NPs has been analyzed. The protective effect of GdVO 4 :Eu 3+ NPs from H 2 O 2 -induced oxidative stress has been estimated using rat hepatocytes and analyzing changes in cells’ mitochondrial potential. It was concluded that the main mechanism of H 2 O 2 decomposition both in aqueous solutions and biological milieu is rather associated with CAT-like reactions that ensure the V 4+ /V 5+ and V 3+ /V 4+ redox cycling.