The exploration of the reversed enantioselectivity of a chitosan functionalized cellulose acetate membranes in an electric field driven process

► A chitosan functionalized cellulose acetate membrane was tested for tryptophan resolution. ► High enantiomeric excess above 90% was obtained in a concentration driven process. ► A negative ee% was obtained in an electric field driven process. ► The phenomenon was discussed with the aid of molecular simulation. ► The solvent evaporation, functionalization are essential for enantio-separation.