Development of An LC-MS Method for The Determination and Identification of Sulfonamide Residues in Propolis

Abstract

A LC-MS method was developed in order quantify any contamination by five sulfonamides including sulfamethazine SMZ,
sulfathiazole STZ, sulfadioxine SDX, sulfadimethoxine SDMX, and sulfamethoxazole SMXZ in propolis samples. The method
showed satisfactory results based on the calibration data where the R2 was > 0.9802 for all the sulfonamides and LOD and LOQ
was within the range 24.26 ng/ml to 31.89 ng/ml and 34.00 ng/ml to 49.63 ng/ml for analysis by tandem mass using a TSQ
7000 instrument. In contrast use of an LTQ Orpitrap instrument gave lower limits of 0.79 ng/ml to 4.39 ng/ml and 2.49 ng/ml to
7.02 ng/ml as for the LOD and LOQ respectively. The methods showed no sign of sulfonamides residues in any of the propolis
samples examined above the LOD. The LTQ Orbitrap method is better suited for applications requiring ultra-low detection lim
its, while the TSQ remains practical for less demanding analytical scenarios.