Abstract: The solvent-detergent (S/D) process is used to inactivate enveloped viruses in plasma products. While concentrations of 1.0% detergent and 0.3% tri-n-butyl phosphate solvent have been considered necessary for robust removal of viral activity, we show the effectiveness of solvent-detergent treatment after fractionation and nanofiltration of an immune gamma globulin preparation, which required significantly reduced concentrations of solvent and detergent. Reduced levels of solvent and detergent lead to greater efficiencies in their removal post-inactivation with the potential for greater yields and decreased processing costs.

Abstract: The solvent-detergent (S/D) process is used to inactivate enveloped viruses in plasma products. While concentrations of 1.0% detergent and 0.3% tri-n-butyl phosphate solvent have been considered necessary for robust removal of viral activity, we show the effectiveness of solvent-detergent treatment after fractionation and nanofiltration of an immune gamma globulin preparation, which required significantly reduced concentrations of solvent and detergent. Reduced levels of solvent and detergent lead to greater efficiencies in their removal post-inactivation with the potential for greater yields and decreased processing costs.

Abstract: Methods for producing biological solutions such as immunoglobulins and in particular anti-D immunoglobulin substantially free of abnormal prion protein resulting therefrom. Specifically provided are methods for aggregation of prions and depth filtration of the biological solution to capture and remove abnormal and if desired, normal prion protein. The prion protein may then be eluted from the depth filter and filter washes and concentrated sufficient for detection at limits currently required by available assays.

Abstract: Methods for producing biological solutions such as immunoglobulins and in particular anti-D immunoglobulin substantially free of abnormal prion protein resulting therefrom. Specifically provided are methods for aggregation of prions and depth filtration of the biological solution to capture and remove abnormal and if desired, normal prion protein. The prion protein may then be eluted from the depth filter and filter washes and concentrated sufficient for detection at limits currently required by available assays.

Abstract: A method of determining levels of extrinsic and intrinsic clotting factors and protein C based upon the reaction rate of the observed clot formation and the first derivative of the reaction rate of observed clot formation is provided. In accordance with the teachings of the invention, the reaction rate of the observed clot formation in a prothrombin time test or an activated partial thromboplastin time assay is determined for both test and normal plasma samples and the reaction rates compared. In another embodiment, the first derivative of the reaction rate of the observed clot formation is determined and the results compared.

Abstract: Disclosed is a procedure for conducting anti-thrombin III assays in which the conventional thrombin-anti-thrombin III treatment step is conducted at a pH of 7.9 to 8.5 maintained at the level by a buffer system comprising a buffering amount of N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid, N-2-hydroxyethylpiperazine-N'-3-propanesulfonic acid, N-tris-(hydroxymethyl)-methyl-2-amino-ethanesulfonic acid, N-tris-(hydroxymethyl)-methylglycine, or N,N-bis (2-hydroxymethyl)-glycine or a salt thereof. The compositions may also contain bacteriostatic agents.