2022, Vol. 26 ›› Issue (21): 3369-3374

Preparation of a polydopamine modified hemerythrin-based nano-oxygen carrier and performance testing

Yang Kang1, Zhao Huimin2, Fan Haojun3, Su Xie4, Wu Guojun5   

Abstract: BACKGROUND: Hemerythrin may be superior to mammalian hemoglobin in terms of molecular stability and low toxicity. Polydopamine modification may further exert its advantages as a hemoglobin oxygen carrier; however, it has not been reported yet.
OBJECTIVE: To prepare a polydopamine modified hemerythrin-based nano-oxygen carrier and examine its performance.
METHODS: The sample of hemerythrin was purified from Eisenia foetida, and bovine hemoglobin was used as a control. The chemical modification reaction was completed with dopamine hydrochloride in a 1:2 mass ratio under pH=8.5-8.8 condition to construct polydopamine modified hemerythrin nanoparticles (PDA-HrNPs) and polydopamine modified bovine hemoglobin nanoparticles (PDA-BHbNPs). The diameter, polymer dispersity index, Z potential, functional molecular group, P50, and Hill coefficient were measured. Two groups of nanoparticles with different mass concentrations [0 (normal control), 1.0, 2.5, 4.0, 5.5 g/L] were co-cultured with vascular endothelial cells or macrophages, respectively. The survival rate of macrophages was measured at 6, 12, and 24 hours after culture. The survival rate of vascular endothelial cells and the concentration of NO in the culture medium were measured at 24 hours after culture.
RESULTS AND CONCLUSION: (1) Infrared spectroscopy of PDA-HrNPs showed that the amide bond bands I and II continued to exist, and a new group band formed by the cross-linking of polydopamine and hemerythrin molecules appeared between 800 and 1000 cm-1. PDA-HrNPs particle size: (202.2±13.64) nm, polymer dispersity index: 0.22±0.05, Z potential: (1.28±0.87) mV, P50: (1.44±0.02) kPa, Hill coefficient: 1.58±0.02. (2) The survival rate of macrophages cultured with two kinds of nanoparticles was lower than that of the normal control group (P < 0.05). The survival rate of macrophages decreased with the increase in time. The survival rate of macrophages at 6 hours in the PDA-HrNPs group was significantly better than that in the PDA-BHbNPs group at the same concentration (2.5, 4.0, and 5.5 g/L) (P < 0.05). (3) After 24 hours of culture, with the increase in the mass concentration of nanoparticles, the survival rate of vascular endothelial cells cultured with two kinds of nanoparticles and the NO concentration in the culture medium decreased. There was no significant difference in the survival rate of cultured cells and the NO concentration in the culture medium between the two kinds of nanoparticles at the same mass concentration (P > 0.05). (4) It is shown that the PDA-HrNPs have good oxygen-carrying activity and safety. The antiphagocytic performance of PDA-HrNPs is better than that of PDA-BHbNPs.
Key words: erythrocyte substitute, hemoglobin-based oxygen carrier, hemerythrin, chemical modification, nanoparticle, cytology test