Abstract: A rapid method was presented for the determination of 7 artificial dyes in plant extracts by ultra-performance liquid chromatography-electrospray ionization quadrupole orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap-MS). Samples were extracted with water, and the extract was cleaned up on a polyamide solid phase extraction (SPE) column and separated by UPLC on a C18 column using a mobile phase consisting of 5 mmol/L ammonium acetate-acetonitrile with gradient elution. Data were collected by ESI Q-Orbitrap MS. The results showed that good linearity was observed in the concentration range from 10 to 500 μg/mL for all 7 artificial dyes, with correlation coefficients (r2) greater than 0.99. The limits of detection (LODs) ranged from 0.001 2 to 0.052 mg/kg. The average recoveries were in the range from 60.8% to 91.8% at 3 spiked levels with relative standards deviation (RSDs) between 2.1% and 6.5%. This method proved to be simple, time saving, accurate, reliable and sensitive and thus can be used for the fast screening and confirmation of artificial dyes in plant extracts.

Key words: plant extracts, artificial dyes, ultra-performance liquid chromatography-quadrupole/electrostatic field orbit trap mass spectrometry, high-resolution mass spectrometry