Chiral recognition of magneto-electropolymerized polyaniline film electrodes

Polyaniline films were prepared by electropolymerization under a magnetic field of 5T parallel (+5T) or antiparallel (-5T) to the faradaic currents. They were used as a modified electrode and their chiral properties were examined for l-3-(3,4-dihydroxyphenyl)alanine (l-DOPA), l-ascorbic acid (l-AA) and d-isoascorbic acid (d-AA) by cyclic voltammetry. The redox currents of l-DOPA on the +5T-film electrode were smaller than those on the -5T-film electrode, and the results for racemic mixture of l- and d-DOPA were the same on the two electrodes. The oxidation current of l-AA on the +5T-film electrode was larger than that on the -5T-film electrode, and the result for d-AA was opposite. These facts demonstrate that the two electrodes have the opposite chirality each other and possess the ability of chiral recognition.