Abstract: Objectives To explore the potential applications and possibility of nanozymes in reducing oxidative stress in blood products. Methods Inorganic nanoparticles with promising antioxidant properties were synthesized using the hydrothermal method. Morphological characterization was performed by transmission electron microscopy. By removing hydrogen peroxide and superoxide anion, we evaluated the antioxidant activities of the nanoparticles. The effects of these nanozymes on the morphology and function of red blood cells(RBCs) were analyzed via optical microscopy and spectroscopic techniques. Results Six distinct types of nanoparticles were synthesized and morphologically characterized, of which Prussian blue, hollow Prussian blue, ultra-small iridium, and ruthenium oxide nanoparticles exhibited more than 75% hydrogen peroxide clearance efficiency at a concentration of 1 mg/mL. Hollow Prussian blue, Prussian blue manganese oxide, ultra-small iridium, and ruthenium oxide nanoparticles demonstrated a superoxide anion clearance rate greater than 65% at the same concentration. When incubated with iridium nanozyme and hemoglobin, the fluorescence spectra remained unchanged. RBCs maintained good structural integrity after co-incubation with iridium nanozyme. Conclusion The synthesized nanozymes have significant hydrogen peroxide and superoxide dismutase activities. Ultra-small iridium nanoparticle, with a size of 1-2 nm, do not compromise the structure of hemoglobin or RBC integrity. These findings preliminarily suggest that the ultra-small iridium nanozyme holds promise for application in combating oxidative damage of RBCs, thereby enhancing the safety and efficacy of blood products.

Key words: Nanozymes, Red Blood Cells, Antioxidants, Feasibility