High Throughput Screening of 86 Kinds of Glucocorticoids in Cosmetics Using QuEChERS and Isotope Dilution-Liquid Chromatography Copuled to High Resolution Time-of-Flight Mass Spectrometry / 分析化学

ABSTRACT

A high throughput screening method based on QuEChERS purification and stable isotope dilution-liquid chromatography coupled to high resolution time-of-flight mass spectrometry was developed for the simultaneous rapid determination of 86 kinds of glucocorticoids (GCs) in cosmetics.The analytes were extracted by acetonitrile, and then the extracts were purified using an improved QuEChERS method.The chromatographic separation was performed on a novel multiple chromatographic retention mechanisms column of Poroshell 120 PFP (100 mm × 2.1 mm, 2.7 μm) with gradient elution using 0.2% (V/V) acetic acid and acetonitrile as mobile phase.The accurate mass database of parent ions and mass spectra library of fragment ions of 86 GCs were established under positive ionization mode with electrospray ionization source.Based on the method described above, the qualitative identifications of the 86 GCs were accomplished without the contrast of standard substances.The results demonstrated that the linear range of this method was from 2 μg/L to 200 μg/L with good correlation coefficients of R2>0.99.The average recoveries of the 86 GCs ranged from 66.2% to 112.8%, and the relative standard deviation (RSDs) was 4.6%-13.9% at three different spiked levels.The limit of detection (LOD) and quantification (LOQ) were 0.006-0.015 mg/kg and 0.02-0.05 mg/kg, respectively.The method is simple, efficient, reliable and accurate, and is suitable for high throughput screening of 86 GCs added illegally in cosmetics.