Patent ID: 6936173

Claim:
A method of removing an unsialylated carbohydrate contaminant from a mixture comprising said contaminant and a sialyl galactoside which is a member selected from sialyl lactosides; glycolipids; liposaccharides; NeuAcα2,3Galβ1,4(Fucα1,3)GlcNAcβ1-Gal-OEt; NeuAcα2,3Galβ1,4(Fucα1,3)GlcNAcβ1,4Galβ1-OEt; and NeuAcα2,3Galβ1,3-Y, in which Y is a saccharide or an oligosaccharide, said method comprising, contacting said mixture with a nanofiltration or reverse osmosis membrane at a pH of from about 1 to about 7, for a length of time sufficient to allow said unsialylated carbohydrate contaminant to pass through said membrane.