| abstract |
Novel stable insulin preparations with protracted action and reduced or no antigenicity are obtained by reacting insulin free of antigenic impurities with an organic compound having basic amino groups, preferably a basic polypeptide or a cleavage product of a basic polypeptide, such as protamine, in a buffered protein dissociating or protein depolymerizing aqueous medium. Examples of preferred protein dissociating or protein depolymerizing media are aqueous solutions containing urea, a lower alkanol dialkylformamide, acetamide, N-alkyl-acetamide or acetonitrile. |