Study on Oxidation Stability and Oxygen Affinity of Hemoglobin During Storage

Abstract

The factors affecting hemoglobin (Hb) oxidation in its short- and long-term storage were investigated. Porcine Hb with different levels of oxygen saturation was stored at 25°C or 4°C for 40 days. The methemoglobin (metHb) content increased rapidly when Hb was at half saturation with oxygen at 4°C, increased gradually with the increase in Hb oxygenation or deoxygenation, and was almost unchanged when Hb was highly oxygenated or deoxygenated. The Hb oxidation was more intense when stored at 25°C. This indicated that highly oxygenated or deoxygenated Hb can be stored short term at 4°C. The accelerated test showed that metHb content was almost unchanged when Hb was highly deoxygenated and stored at 37°C for 7 days; however, the metHb content rapidly increased when Hb was highly oxygenated and stored at 37°C, which indicated that only highly deoxygenated Hb is suitable for long-term storage. Then, the long-term oxidation stability of highly deoxygenated Hb and polymerized hemoglobin was verified; the metHb content of both did not show significant changes at 4°C for 18 months. Moreover, the results in this work indicated that a temperature increasing from 20 to 40°C clearly increased the partial oxygen pressure (P50), which represents decreased oxygen affinity and is beneficial to deoxygenation. Furthermore, P50 was increased when the pH decreased from 9 to 7. Therefore, we concluded that the appropriate high temperature and neutral condition in vitro are conducive to reducing the oxygen affinity of Hb to achieve efficient deoxygenation, which could promote the development of hemoglobin-based oxygen carriers.

The P 50 value detected by the oxygenation-dissociation analyser and blood gas analyser

“…Changes in oxygen affinity of RBCs with storage time have been verified in many studies in the literature [45,46]. In this study, the oxygenation-dissociation analyser can distinguish changes of P 50 values during RBCs storage, while the blood gas analyser failed to reflect the changes.…”

Ferrous hemoglobin and hemoglobin‐based oxygen carriers acting as a peroxidase can inhibit oxidative damage to endothelial cells caused by hydrogen peroxide

“…Spectral analysis of Hb was performed using an SPD‐10AVP plus UV‐VIS spectrophotometer (Shimadzu, Japan) at 37℃. Total Hb concentration and its different oxidation states were measured using a previously reported method 23 . The level of HbFe 4+ was detected by reaction with Na 2 S to form sulfhemoglobin.…”

“…The unpolymerized Hb was removed by ultrafiltration to obtain pPolyHb with a concentration of 11 g/dL, pH 7.6, an average molecular weight of about 650 kDa, a P50 of 30 mm Hg, and a viscosity of 1.3 cP. Other Hb derivatives were prepared using a previously reported method with minor modification 5,23,24 …”

“…Peroxidase activity of pPolyHb Total Hb concentration and its different oxidation states were measured using a previously reported method. 23 The level of HbFe 4+ was detected by reaction with Na 2 S to form sulfhemoglobin. Samples were reacted with 2-mM Na 2 S, and the concentration of sulfhemoglobin was calculated using an extinction coefficient of 10.5 mM −1 at 620 nm.…”

Artificial Organs 2018: A Year in Review

“…Qiuhui Li et al of the Northwest University, Xi'an, China, investigated the oxidation stability and oxygen affinity of hemoglobin (Hb) in storage. The factors affecting hemoglobin (Hb) oxidation in its short‐ and long‐term storage were investigated.…”