A high-throughput UHPLC method for the analysis of 5-nitroimidazole residues in milk based on salting-out assisted liquid–liquid extraction

摘要

Highlights?The determination of eight 5-nitroimidazoles in milk by UHPLC-UV is proposed.?Salting-out assisted liquid–liquid extraction is applied with recoveries≥63%.?Satisfactory linearity (R2≥0.996) and LOD (2–4μg/L) are obtained in milk samples.?The analysis time is 8min and method was validated in cow, goat and ewe milks.AbstractA novel salting-out assisted liquid–liquid extraction (SALLE) method has been developed for the extraction of eight 5-NDZ antibiotics from milk samples prior to their analysis by UHPLC. An exhaustive study of the parameters involved in the SALLE procedure has been carried out, optimizing the extraction solvent volume, the amount of the salt agent, and the centrifugation and vortex timing by an experimental design. After sample treatment, the obtained extract was reconstituted in the mobile phase (6:94 (v/v) acetonitrile/water containing 0