Smart construction of an efficient enantioselective sensing device based on bioactive tripeptide

Recognition of enantiomers using simple and smart devices remains a challenge in modern chemistry, and the development of advanced host materials is the key for the chiral recognition of guest enantiomers. Here, we report a novel enantioselective sensing device based on a bioactive tripeptide, glutathione (GSH). During the construction of the GSH-based enantioselective sensing device, the mercapto group (–SH) of GSH was effectively protected by α-cyclodextrin (α-CD) from being oxidized to disulfide bond (S–S). The α-CD/GSH showed an efficient recognition of tryptophan (Trp) enantiomers due to the intrinsic chiral microenvironment of GSH and the well-retained spatial configuration of GSH. The temperature sensitivity of the α-CD/GSH enantioselective sensing device is also discussed. Finally, the proposed α-CD/GSH was successfully applied in the analysis of the ratio of L- and D-Trp in non-racemic enantiomer mixtures.