[Screening of 17 cephalosporin residues in infant formula milk powder by ultra-high performance liquid chromatography-high resolution mass spectrometry].

A method for the simultaneous determination of 17 cephalosporinsin milk powder by ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) has been developed. After dissolution in water, the homogenized milk powder samples were extracted with acetonitrile to remove impurities such as proteins and the extract was further purified by high-speed centrifugation at low temperature. A C8 chromatographic column was employed to separate the analytes. Quantitative and qualitative analyses were performed in Q Exactive Full-MS/dd-MS scan mode. The results revealed an excellent linear correlation over a wide range of analyte mass concentrations (5-200 μg/L) with coefficients of determination () greater than 0.99 in all cases. The limits of detection (LODs) and quantitation (LOQs) were in the range of 0.0060-0.014 μg/L and 0.71-4.62 μg/kg, respectively. The overall average recoveries were 69.6%-101.4% with RSDs<10%. This method presents the advantages of simple operation, good repeatability, and high resolution, being suitable for the qualitative and quantitative screening of 17 cephalosporin residues in infant formula milk powder.