Rapid determination of sulfonamide residues in honey samples using non-targeted liquid chromatography-high resolution mass spectrometry

Honey is one of the most widespread natural harvest consumed as food and medicine. Many antibacterial groups can be used to protect bees from some bacterial diseases and infections. Among them, sulfonamides are one of the most effective antibacterial drugs used for a long time. While sulfonamides are used by beekeepers, the residues of them may appear in honey with the different levels of residues. These residues in honey at the high level of concentration can be a potential risk to the human body. In this study, a non-targeted liquid chromatography with high resolution mass spectrometry method was designed to discover known and unknown sulfonamide residues in 13 honey samples. This study includes both sample preparation with a modified Quick, Easy, Cheap, Effective, Rugged, and Safe extraction and liquid chromatography analysis. The influences of the chromatographic separation parameters such as flow rate were studied. The detection of sulfonamides was carried out by a reversed-phase chromatographic separation column (a Hypersil Gold C18, 100 mm x 2.1 mm I.D., 1.9 mu m), with gradient elution mode of mobile phase at a flow rate of 0.3 mL/min. Full MS/all-ion fragmentation was used for mass spectrometry acquisition mode. The limit of detection of sulfonamides ranged from 0.02 to 0.12 mu g/kg while the limit of quantification values was between 0.08 and 0.72 mu g/kg. The developed non-targeted analysis was successfully applied for sulfonamide residue determination in honey samples. This study also shows the analysis of the arylamine groups originated from sulfonamides that is a very relevant issue for the toxic side effect of these compounds.