Rapid Screening and Determination of Residual Veterinary Drugs in Milk by Ultrahigh Performance Liquid Chromatography-High-Resolution Quadrupole Time-of-Flight Mass Spectrometry

A rapid screening and determination of 150 veterinary drugs of various classes in milk by UHPLC-high-resolution quadrupole time-of-flight mass spectrometry is proposed. One gram of milk was used for the analysis; the precipitation of proteins and extraction were performed with acetonitrile; the extract was analyzed without purification or preconcentration. Veterinary drugs were identified by accurate masses of analyte ions produced by electrospray ionization, their retention time, and the pattern of ion isotope distribution (mSigma). The quantitative analysis of the detected analytes was carried out by the standard addition method. The limits of detection were 0.1-0.5 ng/g; the analytical ranges were (0.1)1-500 ng/g; the duration of screening was 20-30 min; and the analysis time was 30-40 min. The relative standard deviation of the results for all analytes did not exceed 15%.