Porous polysaccharide scaffold comprising nano-hydroxyapatite and use for bone formation

A porous polysaccharide scaffold obtained by:

• i) preparing an alkaline aqueous solution comprising at least one polysaccharide, a cross-linking agent and a porogen agent,
• ii) transforming the solution into a hydrogel by placing said solution at a temperature from 4° C. to 80° C. for a sufficient time to allow cross-linking of said at least one polysaccharide,
• iii) submerging said hydrogel into a solvent, and
• iv) washing the porous polysaccharide scaffold obtained at step iii),
• wherein the alkaline aqueous solution of step i) further comprises hydroxyapatite and wherein the porous polysaccharide scaffold lacks exogenously added cells and growth factors.