Analysis and occurrence of 14 sulfonamide antibacterials and chloramphenicol in honey by solid-phase extraction followed by LC/MS/MS analysis

A method was developed for the analysis of 14 sulfonamide antibiotics and chloramphenicol in honey. These antibiotics have been banned for use in food-producing animals; yet, their residues were found in many samples, illustrating the need for a multiresidue analysis for these antibiotics in honey. The method described here uses an acid hydrolysis step to liberate the sugar-bound sulfonamides followed by a solid-phase extraction to remove potential interferences. Analysis was by liquid chromatography-electrospray ionization-tandem mass spectrometry in negative mode for all 15 analytes. This MRM method generated two structurally significant transitions per compound, and it was; designed to conform to U.S. Food and Drug Administration MS confirmation guidelines. It also provides 4-EU identification points. One hundred sixteen samples from 25 countries were analyzed, and 38% were found to contain at least one target antimicrobial. Five different target compounds were found in honey from 13 different countries.