A novel bio-based superabsorbent polymer material based on a proteinaceous natural polymer is introduced herein. There is further disclosed a method for the manufacture of such a bio-based crosslinked superabsorbent polymer material. The method includes, but not limited to, introducing polymerizable unsaturated groups onto the natural polymer or its derivative so as to yield a macromonomer. The macromonomer can be formed by covalently binding unsaturated carbon-carbon double bonds to a proteinaceous substrate through a reaction of a selected chemical compound and the amino group on the proteinaceous substrate. The macromonomer is then copolymerized with unsaturated co-monomer(s) to form a crosslinked superabsorbent material.