Fractionation of outdated freeze-dried plasma: a comparative study of cold- and heat-ethanol fractionation procedures.

In a comparative study a total volume of 1435 kg outdated freeze-dried plasma, equivalent to approx. 200,000 kg liquid plasma, was fractionated into albumin (20%): about 30% of the total plasma volume was fractionated following the cold-ethanol procedure and about 70% following the heat-ethanol method. Average albumin recovery following cold-ethanol preparation was 47% of the albumin originally present in the freeze-dried plasma (= 50% of total protein); following heat-ethanol fractionation, 71%. Gelfiltration of heat-ethanol albumin showed a main peak (= 93%) representing albumin monomers and one slightly faster component (= 7%) representing albumin dimers. Gelfiltration of cold-ethanol isolated albumin on the other hand showed four peaks: albumin monomers (= 60%), albumin dimers (= 15%), and two other peaks representing higher molecular weight molecules (= 25%). Hemoglobin present in the reconstituted plasma was reduced about five-fold in the cold-ethanol product and about ten-fold in the heat-ethanol albumin. Stability tests of both products did not differ from equivalent products isolated from normal human plasma. Besides albumin, immunoglobulins may be isolated as Cohn fraction II-III prior to the heating procedure without significant albumin loss.