Rapid screening of multi-class antimicrobial residues in food of animal origin by paper spray mass spectrometry

Abstract

Antibiotics monitoring is of importance in providing healthy diets by preventing animal husbandry from antibiotic misuse. The development of paper spray provides a time-efficient strategy to analyze antibiotics in complex matrices without sample preparation. In this work, paper spray mass spectrometry was applied to identify and quantify nine antimicrobial residues in four antimicrobial families from four kinds of general food matrix, including beef, chicken meat, milk and egg. Samples were directly placed on the paper without any further sample treatment. The limits of detections (LODs) were obtained as 15.0 μg/kg for marbofloxacin in chicken meat, 15.0 μg/kg for difloxacin in chicken meat, 12.5 μg/kg for lincomycin in beef, 12.5 μg/kg for clindamycin in beef, 4.0 μg/kg for amoxicillin in milk, 4.0 μg/kg for penicillin-G in milk, 10.0 μg/kg for cloxacillin in milk, 12.5 μg/kg for minocycline in egg, and 6.2 μg/kg chlortetracycline in egg, respectively. All the LODs were in accordance with the restriction of maximum residue limits (MRLs) of antimicrobial residues announced by the Council Regulation 2377/90/EEC, which suggests a sufficient capability of the paper spray mass spectrometry (PS-MS) method to rapidly screen antimicrobial residues in foods of animal origins.