The use of solid-phase extraction with graphitised carbon for the fractionation and purification of sugars

The unique selectivity, high preparative capacity and chemical inertness of graphitised carbon make it an ideal medium for the solid-phase extraction (SPE) of sugars from dilute solution, and for their analytical and preparative separation from salt, alkali or mineral acid. Graded elution with water containing an organic modifier (such as an alcohol or acetonitrile) permits the separation of groups of oligosaccharides. Acidic sugars are retained by graphitised carbon, while comparable neutral and amino sugars are eluted by water containing an organic modifier; the acidic components are then eluted by the same eluant containing trifluoroacetic acid. As such, graphitised carbon presents a much-needed solid-phase packing for the general clean-up and separation of sugars.