Multi-mycotoxins analysis in liquid milk by UHPLC-Q-Exactive HRMS after magnetic solid-phase extraction based on PEGylated multi-walled carbon nanotubes

A simple and rapid magnetic solid-phase extraction (MSPE) method using PEGylated multi-walled carbon nanotubes magnetic nanoparticles (PEG-MWCNTs-MNP) as absorbents is proposed for isolation and enrichment of aflatoxin B-1 (AFB(1)), aflatoxin B-2 (AFB(2)), aflatoxin G(1) (AFG(1)), aflatoxin G(2) (AFG(2)), aflatoxin M-1 (AFM(1)), aflatoxin M-2 (AFM(2)), ochratoxin A (OTA), zearalenone (ZEA), zearalanone (ZAN), alpha-zeralanol (alpha-ZAL), beta-zeralanol (beta-ZAL), alpha-zeralenol (alpha-ZOL), and beta-zeralenol (beta-ZOL) from liquid milk. Combined with ultra-high performance liquid chromatography Q-Exactive high resolution mass spectrometry, simultaneous qualification of these mycotoxins was achieved with sensitivity and specificity. The proposed method showed a good linearity (R-2 >= 0.995), high sensitivity (limit of detection in the range of 0.005-0.050 mu g/kg and limit of quantification in the range of 0.015-0.150 mu g/kg), adequate recovery (81.8-106.4%), and good repeatability (intra-day precision in the range of 2.1-8.5% and inter-day precision in the range of 3.9-11.7%). It has been successfully applied to the determination of 13 mycotoxins in real liquid milk samples.