Cholesteric Molecular Tweezer Artificial Receptor for Rapid and Highly Selective Detection of Ag in Food Samples.

Chiral cholesteric molecular tweezer was synthesized, and its recognition properties for Ag, Al, Ca etc., were investigated by UV and fluorescence spectra. The results showed that in ethanol/Tris (1/1, /, pH 7.0) buffer solution, the host molecular tweezer had a specific recognition ability for Ag, the detection limit was up to 1 × 10 mol/L, and other metal ions had little effect on Ag recognition. At the same time, the naked-eye detection of Ag was realized by the light red color of the complex solution. Furthermore, the mechanism of recognition of Ag by molecular tweezer was studied by a nuclear magnetic titration test and computer molecular simulation, and a rapid detection method of Ag using host molecular tweezer was established. Through the determination of Ag in milk powder, quinoa and other food samples, it was proved that this novel method had a good application prospect for the detection of Ag in food.