Functionalized vanadium disulfide quantum dots as a novel dual-mode sensor for ultrasensitive and highly selective determination of rutin

[Display omitted] •Novel functionalized β-CD-VS2 QDs was synthesized.•It was used for dual-mode sensing of rutin.•Fluorescence sensing was achieved via quenching of β-CD-VS2QDs.•Direct electrochemical oxidation of rutin at β-CD-VS2 QDs/GCE.•BSA was used to increase selectivity of fluorescence sensor. A reliable electrochemical and fluorometric sensor was proposed for ultrasensitive and selective determination of rutin. It consists of vanadium disulfide quantum dots (VS2 QDs) functionalized with hydropropyl-β-cyclodextrin (β-CD). The as-fabricated sensor was characterized using Transmission electron microscope (TEM), UV–vis spectroscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The electrochemical method is based on the direct oxidation of rutin at β-CD-VS2 QDs/GCE, while the fluorometric method is based on the quenching of β-CD-VS2 QDs fluorescence emission via inner-filter effect (IFE). It was found that the fluorescence emission was decreased with rutin addition in the concentration range of 0.058–45.0 µM with a detection limit (S/N = 3) of 18.0 nM. For the electrochemical analysis, the current response (Ipa) was increased with rutin addition in the concentration range of 0.005–1.4 × 10−8 M with a detection limit (S/N = 3) of 1.6 nM. The proposed dual-mode sensor exhibits many advantages including low detection limit, simplicity, cost-effectiveness, and allows for convenient operation, thereby rendering it a promising and reliable for the detection of rutin in various matrices.