Electrochemical recognition of tryptophan enantiomers using self-assembled diphenylalanine structures induced by graphene quantum dots, chitosan and CTAB

•Electrochemical recognition of Trp isomers at self-assembled diphenylalanine (FF) structures.•The FF structures depend on the material used to induce self-assembly.•This is the first example of a chiral platform constructed with simple building blocks.

Molecular self-assembly offers a promising route to the preparation of advanced materials for the construction of novel chiral sensing devices, and the inspiration for the development of such systems is often derived from simple biological models. Diphenylalanine (FF), an extensively studied short peptide, can self-assemble into highly ordered nano-/micro-structures. Here we report the electrochemical recognition of tryptophan enantiomers using three FF self-assembled structures produced in the presence of graphene quantum dots (GQDs), chitosan (CS) and cetyltrimethylammonium bromide (CTAB). Although the difference in the peak potentials of the enantiomers is very small, enantiomeric differences can be detected by the magnitude of the DPV current signals. The recognition efficiencies of the three self-assembled materials are different, due to the different structures formed during the self-assembly process.

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