A QuEChERS method based on octadecyl-bonded hectorite for the determination of ten mycotoxins in yak ghee

To develop a clean-up material suitable for high-fat food matrices for detecting mycotoxins in yak ghee, an octadecyl-bonded hectorite (Hectorite@NHCO(CH₂)₁₇CH₃) was synthesized through multi-step chemical reactions. A modified QuEChERS-HPLC-MS/MS method for detecting ten mycotoxins in sesame oil in yak ghee was established using Hectorite@NHCO(CH₂)₁₇CH₃ as clean-up agent. It involved extracting mycotoxin contaminants using acidified acetonitrile and employing the Hectorite@NHCO(CH₂)₁₇CH₃ to remove interfering substances from the extract. The purified samples were then analyzed using HPLC-MS/MS. Within a linear range of 1.0-500 μg/kg, there was a good linear relationship between the quantification ion peak area of the target analytes and the corresponding concentrations (R² ≥ 0.9991). The limit of detection (LOD) ranged from 0.10 μg/kg to 18.62 μg/kg and the limit of quantitation (LOQ) ranged 0.32-62.07 μg/kg. The recoveries at low, medium and high concentrations (25, 100 and 500 μg/kg) ranged from 72.2% to 113.9%, with relative standard deviations (RSD) between 3.2% and 17.5%. The intra-day and inter-day precision met experimental requirements. The proposed method was characterized by a high accuracy and precision, and it could cater to the current demand for detecting ten mycotoxins in yak ghee.