FI753503A - - Google Patents

Abstract

1532848 Purifying proteins P G S LINDROOS 19 Nov 1976 [11 Dec 1975] 48376/76 Heading C3H A method for separating iron compounds from the protein in a hemoglobin solution, comprises adding to said solution an organic solvent comprising ethanol in an amount such that the total ethanol content in the solution is at least 40% by volume, adjusting the pH of the liquid to a value lower than 4À5, whereby iron compounds in the solution are agglomerated, and thereafter separating the agglomerated iron compounds from the solution. The solution may be adjusted to a pH value which is less than 4À5 but greater than 2À5. Preferably the pH-value of the solution after agglomeration of the iron compounds is, before or after their separation, raised and wherein any fraction of blood protein precipitated thereby, with iron compounds included therein or adsorbed thereonto, is separated from the mixture. Before or after the agglomeration of iron compounds a minor quantity of broth of blood cells may be added to the solution and any flaky material of fragments of cell membrane formed thereby, together with iron compounds adsorbed thereonto, is then separated from the mixture. The organic solvent preferably includes a minor proportion of glycerin or ethylene glycol or methanol or acetone or ethylacetate or propanol or isopropanol or butanol. The iron compounds may be separated from the solution by centrifuging or a cyclone process or filtering or ultrafiltering or sedimenting or adsorption on to voluminous or solid material, and the protein may be recovered from the solution by precipitation or adsorption on to solid or voluminous material or ultrafiltering or evaporation of the solution or drying or concentration of the solution by means of freezing. The ethanol content in the solution after the agglomeration of iron compounds may be increased before or after their isolation and the fraction of blood protein precipitated thereby, together with any iron compounds included therein or adsorbed thereonto, may then be separated from the mixture. Before addition of ethanol to the solution and lowering of the pH of the solution, the solution is preferably cooled to a temperature of between zero and -20‹ C. and wherein this temperature is maintained during the entire further treatment.