Simultaneous determination of aflatoxin B1 and M1 in milk,fresh milk and milk powder by LC-MS/MS utilising online turbulent flow chromatography

A novel, fully automated method based on dual-column switching using online turbulent flow chromatography followed by LC-MS/MS was developed for the determination of aflatoxin B₁ and M₁ in milk, fresh milk and milk powder samples. After ultrasound-assisted extraction, samples were directly injected into the chromatographic system and the analytes were concentrated on the clean-up loading column. Through purge switch, analytes were transferred to the analytical column for subsequent detection by mass spectrometry. Different types of TurboFlow^TM columns, transfer flow rates and transfer times were optimised. Method limits of detection obtained for AFB₁ and AFM₁ were 0.05 μg kg^–1, and limits of quantification were 0.1 μg kg^–1. Recoveries of aflatoxin B₁ and M₁ were in range of 81.1–102.1% for all samples. Matrix effects of aflatoxin B₁ and M₁ were in range of 63.1–94.3%. The developed method was successfully used for the analysis of aflatoxin B₁ and M₁ in real samples.