Simultaneous determination of eight carbapenems in milk by modified QuEChERS and ultra high performance liquid chromatography coupled with high-field quadrupole-orbitrap high-resolution mass spectrometry

A simple and accurate method of ultra high performance liquid chromatography (UHPLC) coupled with quadrupole-high field Orbitrap high-resolution mass spectrometry (QE HF HRMS) has been developed for analyzing 8 trace-level (mu g/L) carbapenems in milk. Mass spectrometry conditions, chromatographic conditions, extraction solvent and QuEChERS procedures were optimized for determination of 8 carbapenems in milk. Samples were extracted and purified by modified QuEChERS procedure. Good separation for 8 carbapenems s was achieved with a PFP column at 8 min. Method validation results showed the linear ranges are 1-100 mu g/L to 10-1,0 0 0 mu g/L, the correlation coefficients are more than 0.995, and the recoveries of spiked samples are 79.3%-104% with a relative standard deviation less than 15%. This method successfully applied to monitor residue of carbapenems in real milk, four kinds of carbapenems have been detected in 8 sample of 79 collected milks with concentration ranged between 15 mu g/L similar to 3,325 mu g/L.(c) 2022 Elsevier B.V. All rights reserved.