Simultaneous determination of three azo dyes in food product by ion mobility spectrometry

• A simple, rapid and sensitive method was developed to detect three azo dyes by IMS.
• The sample preparation is simple and fast.
• Detection limits were 0.1, 0.05 and 0.2 ppm for orange II, azo rubine and para red.

Color is an important property for food evaluation. Synthetic azo dyes are usually used in food product to obtain better appearance because of their stability and low cost. However, such dyes should be strictly controlled because of their potential threat to human health. A simple, rapid and sensitive method has been developed to determine orange II, allura red, and para red simultaneously by ion mobility spectrometry. The three dyes could be separated at the same time and the migration time of orange II, allura red, and para red are 12.070 ± 0.010, 8.180 ± 0.015, and 11.037 ± 0.016 ms, respectively. The effects of different parameters, such as pH, solvent, percentage of water, were investigated to establish the optimal condition. The detection limits were 0.1, 0.05, and 0.2 μg/mL for orange II, allura red, and para red, respectively. The recoveries of the three azo dyes from jellies were all higher than 81%. The developed method is fast and accurate for the detection of the three synthetic dyes.