A reduced graphene oxide/α-cyclodextrin hybrid for the detection of methionine: electrochemical, fluorometric and computational studies

Abstract

We report on fluorometric and voltammetric detection of L-methionine (Met) based on host–guest interactions between Met and reduced graphene oxide/α-cyclodextrin (rGO/α-CD) hybrid materials. For voltammetric measurements, rGO/α-CD was used as an electrode modification material and successful detection of Met was achieved. Also, rGO/α-CD was used as a fluorescence quencher (turn off) for luminol which was employed as a fluorescent probe. The addition of Met into the same solution gave rise to fluorescence enhancement (turn on) after the host–guest recognition between Met and rGO/α-CD which caused the release of luminol. Interactions of luminol and Met with rGO/α-CD were modeled by molecular docking using AutoDock Vina and the interaction energies were predicted to be −4.3 and −4.4 kcal mol⁻¹, respectively. The proposed biosensor is considered to be a promising model for the detection of Met.