Validation of a gas chromatography-electron capture detection of T-2 and HT-2 toxins in Chinese herbal medicines and related products after immunoaffinity column clean-up and pre-column derivatization

A sensitive, reproducible and accurate gas chromatography-electron capture detection (GC-ECD) method was developed for simultaneous determination of T-2 and HT-2 toxins in Chinese herbal medicines (CHMs) and related products after immunoaffinity column (IAC) clean-up and pre-column derivatization with N-heptafluoro-butyryl imidazole (HFBI). Then, gas chromatography-spectrometry spectrometer (GC–MS) was applied to confirm the positive results and interfering peaks. The limits of detection (LODs) for T-2 and HT-2 toxins were 1.88 and 0.47 ng/g, and the recoveries for different CHMs ranged from 89.2% to 99.1% with relative standard deviation (RSD) <6.0% for T-2 and from 85.9% to 99.0% with RSD <8.8% for HT-2 toxin, respectively. The validated method was successfully applied for the determination of T-2 and HT-2 toxins in 89 Chinese herbal medicines and 10 related products from various sources, where it was found that T-2 and HT-2 toxins were not detected in any of the tested samples. These results were reliable by confirmation using GC–MS. Some unknown peaks were interfering peaks not the target toxins.