Study On Preparation Processing And Evaluating Methods Of Liposome Encapsulated Hemoglobin

The shortage of healthy blood resource and the virus infection have promoted the study of blood substitute. Donor blood is a limited resource and its transfusion is possibly associated with significant adverse effects. An alternative to blood transfusion, based on oxygen-carrying solutions, has been sought by scientists for over a century. So far, several first generation red blood cell substitutes are approaching submission for licensing. While each formulation has its own physical characteristics, biological activities, and adverse reaction profile. In this study, we provide focus on the preparation processing of liposome encapsulated hemoglobin, and we presented some possible interests in the future artificial oxygen carriers'research.About our study:Objective:To determine the effective method to prepare and test hemoglobin vesicles and artificial red blood cells with diameters in micrometer.Methods:Highly purified and concentrated membrane protein was obtained by hypotonic hemolysis of human red cells. According to the principle of interface polymerize method, the hemoglobin and membrane protein water which contained 2, 3–DPG and enzyme was dropped into organic phase with phospholipids. After mixing at high speed, the single global vesicle developed around the non - stable tetramers consisting 2, 3 - DPG and hemoglobin monomers or dimers.Results:Hemoglobin vesicles were global, about 2-5μm in diameter (estimated under electron microscope), with smooth and homogenous surfaces. Transmission electron microscope revealed that single hemoglobin vesicles were global, some of which with smooth surfaces, some slightly unsmooth. The average diameter was 3μm and the smallest was 1μm. Scan electron microscope showed that the electronic density in the vesicle was high and heterogeneous, interlaced with fiber and granules, which hemoglobin was. The envelop rate of artificial blood was 53 % , leakage rate at 4℃in 0. 9 % NaCl was 40.9% after 15 days.Conclusion:Artificial red blood cells can be prepared with diameters around micrometer by double Emulsification.The technologies of modified Hemoglobin,Perfluorocarbons and Hb-Vesicles developed quickly, some of which have already formed into large-scale preparation and production. However, there is no completed evaluation system for the blood substitute at present, and it is still hard to estimate the function of blood substitute completely. Thus,The other significant part of the study is to take the evaluation of liposome encapsulated hemoglobin as a key point, discusses the evaluation parameters of blood substitute and presents the physical and chemical property, the availability, safety and the preservation condition of the blood substitute, which is based on the study in China and abroad and referred to the latest progress all over the world.