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• An Ag-coated nanofiber SERS platform was prepared for rapid nitrite detection. • Electrospraying technique was firstly used to assemble SERS platform. • The Ag-coated nanofiber SERS platform has good homogeneity and reproducibility. • The EF and the LOD was 2.635 × 108, 2.216 × 10−12 M, respectively. • The SERS platform shows good compatibility in nitrite detection for real samples. Nitrite is commonly used as a preservative and color fixative in the meat industry. However, the risk of it transforming into N -nitrosamine restricts its intake. Herein, a novel sensitive Ag-coated nanofiber surface-enhanced Raman scattering (SERS) platform was developed for rapid nitrite detection. The electrospraying technique was firstly used to assemble Ag nanoparticles (NPs) on the nanofibers to obtaine SERS platform. The homogeneity and long-term stability of the SERS platform were evaluated. The limit of detection (LOD) of the SERS platform was estimated to be 2.216 × 10−12 mol/L, corresponding to 15.29 ng·L−1 and good linearity was shown between the relative SERS intensity and nitrite concentration range of 10–1 to 10−4 mol/L. The Ag-coated nanofiber SERS platform was utilized to assay-five common nitrite foods, and the results provided valid evidence for the compatibility of SERS platform in quantitative nitrite detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • L5 can achieve naked-eye recognition for I−. • The mechanism of subject-object recognition was elucidated. • The method can be used for I− detection in food. • L5 has lower detection limit and higher sensitivity. In this study, a cholesteric chiral artificial receptor L5 was synthesized and a rapid method for the detection of iodide ions was established. The addition of L5 to Ethanol/Tris (V/V = 1/1, pH 7.0) solution changed the iodide ion solution from colorless to light yellow to achieve the naked-eye identification. The identification pattern was confirmed with the help of spectral titration, job test and anti-interference test, and it was found that L5 bound to iodide ion in a 1:1 coordination ratio. It was also confirmed that the hydrogen atoms of the amide group of MeO-PhCONH in L5 and the hydrogen atoms of –COOCH 3 in L5 interacted with I− through hydrogen bonding force by 1H NMR titration, infrared spectroscopy, scanning electron microscopy and computer molecular simulation. The detection limit of L5 was 0.025 µmol/L, which could efficiently and conveniently detect iodide ions in food samples. [ABSTRACT FROM AUTHOR]