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Developing chemiresistive devices for the wireless detection of complex analytes has gained considerable interest. In particular, the enantioselective recognition of chiral molecules is still a challenge. Here, we design a hybrid chemiresistive device for the wireless enantioselective discrimination of chiral analytes by combining the enantiorecognition capabilities of an inherently chiral oligomer, that is, oligo‐(3,3'‐dibenzothiophene) (BT2T4) and the insulating/conducting transition of polypyrrole (Ppy). The device is obtained by modifying each extremity of an interdigitated electrode (IDE) with Ppy on the interdigitated area and oligo‐BT2T4 on the connection pads. Due to the asymmetric electroactivity triggered by bipolar electrochemistry, the wireless enantioselective discrimination of both enantiomers of tryptophan and DOPA was achieved. A difference in the onset resistance values was obtained for both enantiomers due to a favorable or unfavorable diastereomeric interaction between the inherently chiral oligomer and the antipode of the chiral molecule. Interestingly, such a device showed a wide quantification range, from μM to mM levels. This work opens up new alternatives to designing advanced wireless devices in enantiorecognition. [ABSTRACT FROM AUTHOR]

In recent years, transductors of chiral information based on conducting polymers have gained considerable attention. In particular, inherently chiral materials, which allow differentiation between the antipodes of a chiral analyte in terms of energetic variations, are highly desired. In this work, we successfully synthesized a novel inherently chiral oligomer based on an indole–benzothiophene core, namely, 2‐([2,2′‐bithiophen]‐5‐yl)‐3‐(2‐([2,2′‐bithiophen]‐5‐yl)benzo[b]thiophen‐3‐yl)‐N‐methylindole (BTIndT4). The electrochemical characterization evidences a stabilization of electrogenerated radical cations due to the presence of the indole group, which guides the oligomerization, producing well‐ordered polymeric matrices. Furthermore, the in situ electrochemical conductance analysis demonstrates a simultaneous intrachain and interchain transfer of charge carriers. Finally, the highly efficient enantiorecognition capabilities of the antipodes of the oligo‐BTIndT4 films toward the enantiomers of tryptophan and 3,4‐dihydroxyphenylalanine (DOPA), as model chiral analytes, were demonstrated. [ABSTRACT FROM AUTHOR]