Adsorption and hydrolytic activity of trypsin on a carboxylate-functionalized cation exchanger prepared from nanocellulose

► A novel hydrogel, PAPGNC was synthesized by graft copolymerization technique. ► PAPGNC was characterized using XRD, SEM, and FTIR techniques. ► Adsorption characteristics of an enzyme, trypsin (TRY) onto PAPGNC were investigated. ► PAPGNC can be used in the recovery of TRY from aqueous solutions. ► Regeneration of spent adsorbent was possible with 0.1 M KSCN.