Characterization and Biosafety Evaluation of Hemoglobin-Based Oxygen Carriers Coated with Polydopamine

Hemoglobin-polydopamine particles (Hb-PDA) have shown high stability, with polydopamine (PDA) serving as a protective layer and antioxidant. However, the effects of the PDA coating on the properties and in vivo biosafety of Hb-PDA remain unclear. This work was conducted to characterize Hb-PDA and evaluate its biosafety. Hb-PDA exhibited negative surface charge and their infusion did not cause blood immunotoxicity or significant tissue injury. Hb-PDA were not phagocyted after co-incubation with macrophages for 3 h. Moreover, the particles showed the highest accumulation in the lungs, and a prolonged retention in major organs. It was also found that the particles were cleared by macrophages in splenic tissue and Kupffer cells in hepatic tissue. In summary, this research showed that Hb-PDA has high dispersion stability, low in vivo toxicity, and extended retention, illustrating its potency as a biosafe oxygen carrier.