Abstract: Solid, bioabsorbable materials for use as wound dressings comprise at least 50% by weight of a mixture of xanthan and at least one galactomannan, such as guar gum or locust bean gum. The weight ratio of xanthan: total galactomannans is in the range 1:99 to 99:1, preferably 10:99 to 99:10. The material is preferably made in the form of a sponge by freeze drying a mixed aqueous gel of the xanthan and galactomannans.

Abstract: The invention provides a method of preparing water-insoluble polysaccharide sponges, and sponges obtained by means of the method. The method comprises: (a) providing an aqueous solution of a soluble polysaccharide; (b) freezing the solution; (c) treating the frozen solution with a water-miscible organic solvent such as isopropanol to effect solvent exchange for the water in the frozen solution; and (d) drying the resulting polysaccharide material. The organic solvent contains a cross-linking agent such as calcium chloride to render the polysaccharide water-insoluble in the solvent-exchange step (c). The resulting materials are more conformable and less friable than freeze-dried polysaccharide sponges.