 The historic Alcian Blue varied so much batch to batch that only the 8GX (e.g.not even the 8GS) batch produced by ICI was later decided to be the biologically useful ones.Commercially available batches usually contained about 49% of the actual dye and rest used to be Sulfate, boric acid, dextrin and other impurities and by various extraction methods up to 80% pure extracts can be made.