Polydopamine and silica nanoparticles magnetic solid phase extraction coupled with liquid chromatography-tandem mass spectrometry to determine phenolic acids and flavonoids in fruit wine.

Magnetic solid phase extraction (MSPE) have been widely applied in a variety of sample preparation techniques. Herein, FeO@pDA as the sorbents for MSPE, were developed for the determination of phenolic acids and flavonoids in fruit wine samples in combination with LC-MS/MS. The FeO@pDA were characterized by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), Superconducting Quantum Interference Device Magnetometer (SQUID) and thermogravimetric analysis (TGA) in detail. In the present study, a new, rapid, and efficient MSPE by LC-MS/MS was established for the extraction and sensitive detection of phenolic acids and flavonoids. Under the optimized condition of extraction procedure including the pH value of 4.0, 10 mg of FeO@pDA, 60 s extraction time, and 600 μL desorption solvent volume, good responses were investigated. Results showed that the limits of detection (S/N = 3) for phenolic acids and flavonoids were in the range of 0.01-0.29 ng/ mL. The correlation coefficients of all analytes were more than 0.9985. The method was satisfactorily used for the detection of eleven analytes, and the recoveries of these targets for the two spiked wines (white grape wine and litchi wine) ranged from 80.03 to 116.68% and from 84.00 to 116.1%, respectively.