Antioxidant enzymes immobilized on gold and silver nanoparticles enhance DNA repairing systems of rat skin after exposure to ultraviolet radiation.

The aim of the study was to investigate in vivo whether the application of immobilized superoxide dismutase (SOD) and catalase (CAT) could enhance DNA repairing systems and reduce level of CPD (cyclobutane pyrimidine dimers) and 6-4PP ((6-4) pyrimidine-pyrimidone photoproducts), and whether the immobilization on gold (AuNPs) and silver (AgNPs) nanoparticles affects the outcome. The study presents secondary analysis of our previous research. Three-day application of SOD and CAT in all forms of solution decreased the levels of CPD and 6-4PP boosted by UV irradiation.

The effect of immobilized antioxidant enzymes on the oxidative stress in UV-irradiated rat skin.

Superoxide dismutase (SOD) and catalase (CAT) immobilized on gold nanoparticles (AuNP) and silver nanoparticles (AgNP) nanoparticles were used to reduce UV radiation-induced oxidative stress in rat skin. The antioxidant influence of the enzymes was investigated on level of malondialdehyde, 8-hydroksy-2'deoksyguanozine, myeloperoxidase, total antioxidant capacity, SOD2 and CAT activity and expression, and glutathione and glutathione peroxidase activity. The application of immobilized SOD and CAT on UV-irradiated skin reduced malondialdehyde and 8-hydroksy-2'deoksyguanozine levels also SOD and CAT activity and expression increased.

A Study of the Activity of Recombinant Mn-Superoxide Dismutase in the Presence of Gold and Silver Nanoparticles.

Superoxide dismutase (SOD) is one of the best characterized enzyme maintaining the redox state in the cell. A bacterial expression system was used to produce human recombinant manganese SOD with a His-tag on the C-end of the protein for better purification. In addition, gold and silver nanoparticles were chemically synthesized in a variety of sizes, and then mixed with the enzyme for immobilization.

Immobilization of Recombinant Human Catalase on Gold and Silver Nanoparticles.

Human catalase cDNA was cloned into a pEX-C-His vector. Purified recombinant catalase was immobilized on nanoparticles. Gold and silver nanoparticles were synthesized in a variety of sizes by chemical reduction; no agglomerates or aggregates were observed in any of the colloids during dynamic light scattering or scanning transmission electron microscopy analysis.