Preserving a hemoglobin blood substitute with a transparent overwrap

Abstract

The invention relates to a method for preserving the stability of a hemoglobin blood substitute comprising maintaining the hemoglobin blood substitute in an atmosphere substantially free of oxygen. The invention also involves a method for producing a stable polymerized hemoglobin blood-substitute from blood. The method of this invention includes mixing blood with an anticoagulent to form a blood solution, washing the red blood cells in the blood solution and then separating the washed red blood cells from the white blood cells. This method also includes disrupting the red blood cells to release hemoglobin and form a hemoglobin solution, which is then treated by high performance liquid chromatography to form a hemoglobin eluate. The hemoglobin eluate is then deoxygenated, contacted with a first sulfhydryl compound to form an oxidation-stabilized deoxygenated hemoglobin solution, and mixed with a cross-linking agent to form a polymerization reaction mixture, which is then polymerized. The polymerized hemoglobin solution is then diafiltered with a physiologic solution and with a sulfhydryl compound, whereby the polymerized hemoglobin solution is made physiologically acceptable, and whereby the sulfhydryl compound scavenges oxygen, to form a stable polymerized hemoglobin blood-substitute, which is then packaged and stored in an atmosphere substantially free of oxygen.

The invention claimed is:  
     
         1 . A method for preserving a deoxygenated hemoglobin blood substitute comprising maintaining the deoxygenated hemoglobin blood substitute in an oxygen barrier film overwrap including a transparent laminate material having a thickness of between about 0.001 and about 0.01 inches, said laminate material including an ethylene vinyl alcohol layer and having an oxygen permeability of less than about 0.01 cubic centimeters per 100 square inches over 24 hours at one atmosphere and at room temperature.  
     
     
         2 . The method of  claim 1  wherein the laminate material further includes a polyolefin layer.  
     
     
         3 . The method of  claim 1 , wherein the polyolefin layer and the ethylene vinyl alcohol layer are co-extruded.  
     
     
         4 . The method of  claim 1 , wherein the laminate further includes a linear low density polymer layer.  
     
     
         5 . The method of  claim 1  wherein the hemoglobin blood substitute is maintained under a nitrogen, argon or helium atmosphere.  
     
     
         6 . A preserved deoxygenated hemoglobin blood substitute, comprising: 
 a) a deoxygenated hemoglobin blood substitute contained within a primary package; and    b) a transparent oxygen barrier film overwrap package that includes a first polymer layer, an oxygen barrier film and a second polymer layer, said oxygen barrier film including ethylene vinyl alcohol and having an oxygen permeability of less than about 0.01 cubic centimeters per 100 square inches over 24 hours at one atmosphere and at room temperature, within which the deoxygenated hemoglobin blood substitute and the primary package are sealed, thereby preserving the deoxygenated hemoglobin blood substitute in an environment that is substantially free of oxygen.    
     
     
         7 . The preserved deoxygenated blood substitute of  claim 6  wherein the first polymer layer includes a polyolefin.  
     
     
         8 . The preserved deoxygenated blood substitute of  claim 6 , wherein the first polymer layer and the oxygen barrier layer are co-extruded.  
     
     
         9 . The preserved deoxygenated blood substitute of  claim 6 , wherein the second polymer layer includes a polyolefin.