Lyophilization of red blood cells

Claim 2

A process for the lyophilization of erythrocytes, comprising immersing a plurality of erythrocytes in a buffered solution which includes: a monosaccharide which is present in the solution in a concentration of from about 7.0 to 37.5%; a polymer having a molecular weight of from about 5K to about 80K which is present in a concentration of from about 0.7% up to saturation in the solution; a polyanion which is present in a concentration of from 0.01 weight percent up to saturation in the solution; freezing the solution; and drying the erythrocytes by sublimation of the water.

Claim 3

The process of claim 1 wherein the monosaccharide is selected from the group consisting of pentoses and hexoses.

Claim 4

The process of claim 1 wherein the monosaccharide is selected from the group consisting of xylose, glucose, ribose, mannose and fructose.

Claim 5

The process of claim 1, 2 or 3 wherein the polymer is selected from the group consisting of polyvinylpyrrolidone, dextran and gelatin.

Claim 6

The process of claim 1, 2 or 3 wherein the polyanion is a compound having anionic groups which are phosphate, sulfate or carboxylate groups.

Claim 7

The process of claim 4 wherein the polyanion is a compound having anionic groups which are phosphate, sulfate or carboxylate groups.

Claim 8

The process of claim 1, 2 or 3 wherein the polyanion is selected from the group consisting of pyrophosphate, tripolyphosphate, phosphorylated inositols, 2,3 diphosphoglycerate, adenosine triphosphate, phosphorylated dextran, heparin and polycarboxylic acids.

Claim 9

The process of claim 4 wherein the polyanion is selected from the group consisting of pyrophosphate, tripolyphosphate, phosphorylated inositols, 2,3 diphosphoglycerate, adenosine triphosphate, phosphorylated dextran, heparin and polycarboxylic acids.

Claim 10

A process for the lyophilization of erythrocytes having a cell membrane, comprising: immersing a plurality of erythrocytes in a buffered solution which includes (a) monosaccharide selected from the group consisting of xylose, glucose, ribose, mannose and fructose, the monosaccharide being present in the solution in a concentration of from about 7.0 to 37.5%; (b) a biocompatible polyanion selected from the group consisting of pyrophosphate, tripolyphosphate, phosphorylated inositols, 2,3 diphosphoglycerate, adenosine triphosphate, phosphorylated dextran, heparin and polycarboxylic acids, the polyanion being present in the solution in a concentration of at least 0.01 weight percent; (c) a polymer selected from the group consisting of polyvinylpyrrolidone and dextran, the polymer being present in the solution in a concentration of at least 0.7%; freezing the solution, and drying the erythrocytes by sublimation of the water.

Claim 11

A process for the lyophilization of erythrocytes having a cell membrane, comprising: immersing a plurality of erythrocytes in a buffered solution which includes (a) monosaccharide selected from the group consisting of xylose, glucose, ribose, mannose and fructose, the monosaccharide being present in the solution in a concentration of from about 7.0 to 37.5%; (b) a biocompatible polyanion selected from the group consisting of pyrophosphate, tripolyphosphate, phosphorylated inositols, 2,3 diphosphoglycerate, adenosine triphosphate, phosphorylated dextran, heparin and polycarboxylic acids, the polyanion being present in the solution in a concentration of at least 0.01 weight percent; (c) a polymer selected from the group consisting of polyvinylpyrrolidone and dextran, the polymer being present in the solution in a concentration of at least 0.7%; freezing the solution, and drying the erythrocytes by sublimation of the water.