Auramine O quantitation in chicken meat and animal feedstuffs by LC – MS/MS

Abstract

Auramine O is a dye on the list of prohibited substances for use in food and livestock (animal feed) but is still widely used. The main objective of this study is to develop a LC-MS/MS method with high requirements of high sensitivity, accuracy and simple to provide the authorities with an effective tool to control the use of this banned substance. The target samples are animal feed, chicken meat, and chicken skin. The samples were extracted by acetic acid 1% in ACN, and then the extracts were cleaned up and concentrated using strong cation exchange catridges (with silica as support material) before chromatographic analysis. The mobile phase was ammonium acetate 5 mM in H2O with formic acid 0.1% in ACN. Under the optimized detection conditions, the linear range for Auramine O was 0.10 ÷ 500 ppb, and the linear correlation coefficients were found to be more than 0.998. The limit of quantification of Auramine O was 0.2 ppb. The recoveries of Auramine O ranged from 77 ÷ 99% with relative standard deviations (RSD) of 1.00 ÷ 2.10%. This method is simple, effective, sensitive, and suitable for determining and confirming Auramine O in animal feeds and other food samples.