Novel membrane processes for the effective enantioresolution of racemic mixtures have been evaluated. The incorporation of human serum albumin (HSA) in the strip solution of a permeation cell resulted in the partial optical resolution of a racemic tryptophan mixture, as the permeation of L-tryptophan, which binds to HSA more strongly, was enhanced selectively over that of D-tryptophan. A second approach in which a racemic mixture was introduced to the strip solution prior to the experiments showed better performance by selectively decreasing the flux of the more weakly bound D-tryptophan. The highest enantioselectivity of similar to 9.76 was achieved with a third, novel design consisting of two permeation cells in series, which can encompass the advantages of affinity dialysis. An industrial scale unit is proposed based on this concept and a suitably validated mathematical model. (C) 2010 American Institute of Chemical Engineers AIChE J, 57: 1154-1162, 2011