ABSTRACT
Objective@# To develop a magnetic solid-phase extraction combined with gas chromatography-tandem mass spectrometry (GC-MS/MS) based on pyrrole-modified magnetic nanoparticles to determine 16 types of phthalic acid esters (PAEs) in commercial liquors.@*Methods @#Fe3O4 magnetic nuclei were prepared by hydrothermal synthesis, and the polypyrrole-modified magnetic nanomaterials were prepared with the chemical oxidation method. Magnetic solid-phase extraction of beer, grape wine, rice wine and Chinese spirits was performed at 10% alcohol by volume, extraction duration of 20 min and ethyl acetate elution of 10 min, followed by addition of 1 g NaCl for reduction of emulsification effect. The 16 types of PAEs were determined using GC-MS/MS with DB-5MS capillary column (30 m×250 μm, 0.25 μm) under the mode of electron impact ionization (EI) and dynamic multiple reaction monitoring (dMRM), with quantitative analysis using the external standard method. The standard curve, detection limit, spike recovery rate and precision of GC-MS/MS for determination of 16 types of PAEs were evaluated.@*Results@#Pyrrole was successfully embedded onto the surface of magnetic nanoparticles in the form of polymer, and the magnetic nanoparticles modified by polypyrrole were well characterized, showing unapparent matrix and emulsification effects. There was a good linear relationship for the 16 types of PAEs at 50 to 5 000 ng/mL (r=0.999 5-0.999 9), and the spike recovery rate of 16 types of PAEs ranged from 71.61% to 110.50% at 100, 500 and 1 000 μg/kg, with relative standard deviations of 3.78% to 7.41%, detection limits of 0.02 to 1.47 μg/kg. PAEs were detected in 20 out of 50 liquor samples, with 30.00%, 60.00%, 40.00% and 70.00% detection rates in beer, grape wine, rice wine and Chinese spirits, respectively. @*Conclusions@#This method is sensitive to determine 16 types of PAEs in liquor samples, with unapparent matrix and emulsification effects, and the polypyrrole-modified magnetic composite nanoparticles present high adsorption of PAEs in liquor samples, which is feasible for monitoring of PAEs in multiple types of liquor samples.