METHOD OF SEPARATING GLYCOSYLATED AND NON-GLYCOSYLATED PROTEINS

This invention relates to a method for separating glycosylated prolactin from non-glycosylated prolactin. The method comprises the following steps: 1) equilibrating the prolactin containing solution with an equilibrating solution containing at least one organic solvent; 2) adding the equilibrated prolactin solution onto a chromatographic column containing a packing for the ion-exchange affinity separation of glycosylated and non-glycosylated prolactin; 3) eluting the glycosylated prolactin from the chromatographic column with a sufficient quantity of a first eluting solution containing at least one organic solvent and with or without at least one salt, wherein the salt concentration and/or organic solvent concentration and/or pH are appropriate for the eluting of glycosylated prolactin being substantially free of non-glycosylated prolactin; and 4) eluting the non-glycosylated prolactin from the chromatographic column with a sufficient quantity of a first eluting solution containing at least one organic solvent and with or without at least one salt, wherein the salt concentration and/or organic solvent concentration and/or pH are appropriate for the eluting of non-glycosylated prolactin being substantially free of glycosylated prolactin.