Preparation Of Pegylated Bovine Hemoglobin And Its Effect On Hemorrhagic Shock

The preferential material of PEGylated heamoglobin is human heamoglobin(h Hb) which is obtained from the out-dated human blood. However, the use of human heamoglobin is constrainted for the deficit and high oxygen affinity. The PEGylated bovine heamoglobin(b Hb) has been synthesized using b Hb for the low oxygen affinity and the adequate supply. The physical and chemical properties, structure and function of PEGylated bovine heamoglobin were clarified for providing datum of sloving raw material and developing HBOCs of low P50.The PEGylated heamoglobin with the advantage of high hydrodynamic volume, high viscosity and high colloidal osmotic pressure(COP) has been evaluated as a potential blood substitute. In this research, the PEGylated human heamoglobin(EAF-PEG-h Hb) and PEGylated bovine heamoglobin(EAF-PEG-b Hb) were obtained. The process as followed: the sulfydryl including sulfhydrylated amino-group by the 2-iminothiolane(IT) and the natural sulfydryl at Cys-93 were connected with maleimide-activated polyethylene glycol(MAL-PEG) to obtain PEGylated Hb. The physical, chemical and structural properties of EAF-PEG-Hb were measured for clarifying the P50 of EAF-PEG-b Hb. Then, the mice severally were resuscitated with Ringer’s lactate(LR), EAF-PEG-h Hb and EAF-PEG-b Hb after a severe pressure-controlled haemorrhage. The biological function of EAF-PEG-h Hb and EAF-PEG-b Hb could be clarified by the mice of severe hemorrhagic shock.As we expected, the P50 and COP of EAF-PEG-b Hb was higher than that of the EAF-PEG-h Hb. This result was expectant. However, the rate of autoxidation of EAF-PEG-b Hb was more rapid than the control sample of EAF-PEG-h Hb.Comparing with EAF-PEG-h Hb, the EAF-PEG-b Hb was same in the MAP and was ascendant in improving acidosis of hemorrhagic shock. It was ascendant in improving acidosis of hemorrhagic shock for its the lower oxygen affinity and the higher COP and viscosity.