Abstract: Novel monofunctional polyethylene glycol aldehyde for pegylating therapeutically active proteins to produce pegylated protein conjugates which retain a substantial portion of their therapeutic activity and are less immunogenic than the protein from which the conjugate is derived and a new synthesis for preparing such aldehydes.

Abstract: The use of hemoglobin-polymer conjugates to enhance antitumor therapy in mammals is disclosed. The methods include administering an effective amount of an antitumor therapy such as radiation in combination with hemoglobin conjugated to a substantially non-antigenic polymer.

Abstract: The use of hemoglobin-polymer conjugates to enhance antitumor therapy in mammals is disclosed. The methods include administering an effective amount of an antitumor therapy such as radiation in combination with hemoglobin conjugated to a substantially non-antigenic polymer.

Abstract: Hemoglobin-containing solutions containing polyalkyene oxide-conjugated hemoglobin having a molecular weight greater than about 85,000 daltons and a degree of substitution of at least five polyalkylene oxide conjugates per hemoglobin molecule are described that are not associated with hemoglobinuria in mammals. A method of simultaneously fractionating and purifying polyalkylene oxide-conjugated hemoglobins is also disclosed.

Abstract: The present invention relates to chemically modified hemoglobin produced by a novel and efficient method in which stroma-free hemoglobin is first effectively deoxygenated and reduced and then conjugated with a polyalkylene oxide such as polyethylene glycol (PEG) under conditions which maintain the structural integrity of the heme oxygen binding site. In specific, preferred embodiments of the invention, the deoxygenation and reduction is performed under an inert atmosphere by the amino acid cysteine. In additional specific, preferred embodiments, the structural integrity of the heme oxygen binding site is maintained by a high anionic concentration in the reaction mixture. In further preferred specific emodiments of the invention, the polyalkylene oxide is polyethylene glycol; in still further preferred specific embodiments of the invention, the polyalkylene oxide is linked to hemoglobin via a urethane (carbamate) linkage.

Abstract: Hemoglobin-containing solutions containing polyalkylene oxide-conjugated hemoglobin having a molecular weight greater than about 85,000 daltons and a degree of substitution of at least five polyalkylene oxide conjugates per hemoglobin molecule are described that are not associated with hemoglobinuria in mammals. A method of simultaneously fractionating and purifying polyalkylene oxide-conjugated hemoglobins is also disclosed.

Abstract: Methods are disclosed for separating hemoglobin from erythrocytes by contacting erythrocytes with a hypotonic buffer solution at a rate sufficient to render the release of hemoglobin from said erythrocytes without significant lysis. The hemoglobin is then separated from the erythrocytes. Methods are also disclosed for purifying hemoglobin solutions of DNA, endotoxins and phospholipids by contacting the hemoglobin solutions with an anion exchange medium.

Abstract: The present invention relates to chemically modified hemoglobin produced by a novel and efficient method in which stroma-free hemoglobin is first effectively deoxygenated and reduced and then conjugated with a polyalkylene oxide such as polyethylene glycol (PEG) under conditions which maintain the structural integrity of the heme oxygen binding site. In specific, preferred embodiments of the invention, the deoxygenation and reduction is performed under an inert atmosphere by the amino acid cysteine. In additional specific, preferred embodiments, the structural integrity of the heme oxygen binding site is maintained by a high anionic concentration in the reaction mixture. In further preferred specific embodiments of the invention, the polyalkylene oxide is polyethylene glycol; in still further preferred specific embodiments of the invention, the polyalkylene oxide is linked to hemoglobin via a urethane (carbamate) linkage.