Multi-mycotoxins analysis in ginger and related products by UHPLC-FLR detection and LC-MS/MS confirmation

- Ginger and related products are widely used all over the world.
- AFs and OTA are highly toxic mycotoxins, which could easily contaminate ginger.
- The method based on IAC-SPE for detection of AFs and OTA by UHPLC-FLR was established.
- The positive samples were confirmed by LC-ESI-MS/MS.

The aim of this study was to optimize and validate a powerful method for the simultaneous analysis of aflatoxins B1 (AFB1), B2 (AFB2), G1 (AFG1), G2 (AFG2) and ochratoxin A (OTA) in ginger and related products collected from local markets in Beijing, China. The optimized analytical procedure was based on immunoaffinity column (IAC) clean-up, followed by ultra-high performance liquid chromatography with fluorescence (UHPLC-FLR) detection. Limits of detection (LOD) and quantification (LOQ) for the five mycotoxins were 0.005-0.2 and 0.0125-0.5 μg kg−1, respectively. The average recoveries ranged from 84.2 to 97.3% with relative standard deviations (RSDs) from 0.63 to 7.86% at three spiking levels. Good linearity was observed for the analytes with correlation coefficients all higher than 0.9995. The established method was applied to 30 samples of 10 different species of ginger and related products, and all positive samples were confirmed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The results showed that 5 samples of ginger products were contaminated with AFB1 at 0.13-1.38 μg kg−1, while 3 samples of ginger and 2 samples of ginger products were contaminated with OTA at 0.31-5.17 μg kg−1. All the contamination levels were below the legally allowable limits.