Enantioselective recognition of amino acids based on molecularly imprinted polyaniline electrode column

A novel molecularly imprinted polyaniline (PAn) electrode column is introduced as a new technique for the enantioselective recognition of amino acids. The principle of the molecularly imprinted electrode column is based on the reversible doping/de-doping property of PAn. PAn is an organic semiconductor and thus from an electrochemical point of view the column packed with PAn can be regarded as a packed-bed electrode of a three-electrode arrangement. The electric potential of this column can be easily controlled by a potentiostat. Various important factors influencing the performance of the molecularly imprinted PAn column have been investigated using fluorescence spectrometry in conjugation with the electrochemical quartz crystal microbalance (EQCM) technique. The advantage of this method proposed over previously reported is that the enantio-recognition can be performed in a high efficiency without requiring an expensive chiral column. Especially, the ejection and re-binding of amino acids can be accomplished by adjusting the potential applied on the column packed with molecularly imprinted PAn.