Preparation And Functional Evaluation Of Dextran-hemoglobin

Hemoglobin-based oxygen carriers have been investigated to solve the problems of hemoglobin, such as short half-life, instability and renal toxicity. Dex-Hb, which hemoglobin conjugates with dextran, has been developed for several years. However,Dex-Hb had a low P50, which limited Dex-Hb to release oxygen in vessel effectively.The aim of the current study is to analyze the preparation and the property of Dex-Hb synthesized by the dialdehyde method as a potential blood substitute.Through optimizing the ratio of reactant, the dosage of periodate and the time of oxidation, Dex-Hb without residual hemoglobin was produced by the method which less materials. And Dex-Hb produced by the method of closed sulfhydryl had a high P50, which was beneficial for delivering oxygen. Dex-Hb had an enhancement in molar weight The COP of Dex-Hb displayed a slight increase and the viscosity displayed a notable increase compared. It suggested that Dex-Hb had the ability of expanding blood volume and it was not able to cause hypertension. The autoxidation rate constant of Dex-Hb was lower than that of hemoglobin, which decreased the toxicity of hemoglobin. Structurally, the secondary structure of Dex-Hb was not destroyed by the conjugation and Dex-Hb turned towards R state. Functionally,Dex-Hb has a high oxygen affinity and was sensitive to the allosteric effectors. At the same time, Dex-Hb was blood compatible, which had no difference on aggregation and hemolytic potential. In the end, via the hemorrhagic shock model, it was proved that Dex-Hb was able to recover the systematic and microcirculatory circulation, and prevent tissue injury.In conclusion, Dex-Hb is potential to becomes a potential blood substitute.Through the study, there are research foundations for other blood substitute.