Development and validation of a multi-residue and multiclass ultra-high-pressure liquid chromatography-tandem mass spectrometry screening of antibiotics in milk

24 25 A multi-residue screening method for 33 antibiotics from five different families 26 was employed to simultaneously determine sulphonamide, tetracycline, macrolide, 27 quinolone and chloramphenicol antibiotics using ultra high pressure liquid 28 chromatography tandem mass spectrometry. A simple sample preparation method was 29 developed using protein precipitation, centrifugation and solid phase extraction and was 30 optimised to achieve the best recovery for all compounds. The methodology was 31 validated for quantitative screening methods, by evaluating the detection capability 32 (CCβ), specificity, selectivity, precision, applicability and ruggedness. Precision, in 33 terms of relative standard deviation, was under 21% for all compounds. Because CCβ 34 was determined for screening purposes and, according to maximum residue limit, the 35 limit of detection of the method was calculated and ranged from 0.010 μg kg to 3.7 μg 36 kg. This validation provided evidence that the method is suitable to be applied in 37 routine analysis for the detection of antibiotics in bovine, caprine and ovine milk. 38 ______________________________________________________________________ 39 M AN US CR IP T AC CE PT ED ACCEPTED MANUSCRIPT