Preparation of CS/GPTMS hybrid molecularly imprinted membrane for efficient chiral resolution of phenylalanine isomers

An enantioselective chitosan (CS)/γ-glycidoxypropyltrimethoxysilane (GPTMS) hybrid membrane was prepared in aqueous phase by a modified sol–gel process using CS as bulk polymer, l-phenylalanine (l-Phe) as imprinting molecules and GPTMS as crosslinking agent. SEM-EDX characterization reveals the dense structure of the membrane and homogeneous distribution of silica in chitosan matrix. The chiral separation ability of CS/GPTMS hybrid molecularly imprinted membranes towards the underivatized d,l-Phe aqueous mixture was evaluated by permeation and binding experiments. Significantly improved selectivity with a separation factor αd/l up to 4.5 has been achieved.