Multiresidue LC – MS / MS analysis of cephalosporins and quinolones in milk following ultrasound‐assisted matrix solid‐phase dispersive extraction combined with the quick, easy, cheap, effective, rugged, and safe methodology

A sensitive and selective confirmatory method for milk‐residue analysis of ten quinolones and eight cephalosporins by LC ‐ MS / MS has been developed herein. For the chromatographic separation of target analytes, a P erfectsil ODS ‐2 (250 × 4 mm, 5 μm) analytical column was used and gradient elution was applied, using a mobile phase of 0.1% w/w TFA in water and 0.1% w/w TFA in ACN . Ultrasound‐assisted matrix solid‐phase dispersion procedure was applied for the extraction and clean‐up procedure of antimicrobials agents from milk matrix using a mixture of B ond E lut P lexa sorbent and Q u EC h ERS . The method was validated meeting the E uropean L egislation determining selectivity, linearity response, trueness, precision (repeatability and between‐day reproducibility), decision limit, detection capability, and ruggedness following the Y ouden approach. Recoveries of all antibiotics ranged from 81.7 to 117.9%, while RSD values were lower than 13.7%. Limits of quantification for all examined compounds ranged from 2.4 to 15.0 μg/kg, substantially lower than the maximum residue limits established by the E uropean U nion (30–100 μg/kg).