South African Journal of Chemistry
On-line version ISSN 1996-840X
SICHILONGO, Kwenga F.; MUCKOYA, Vallerie A. and NINDI, Mathew M.. A rapid and sensitive LC-MS/MS method for the determination of multi-class residues of antibiotics in chicken liver. S.Afr.j.chem. (Online) [online]. 2015, vol.68, pp. 01-06. ISSN 1996-840X. http://dx.doi.org/10.17159/0379-4350/2015/v68a1.
A very sensitive, simple and cost-effective liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for the determination of multi-class antibiotics in chicken liver was developed. The drugs under consideration were sulfaguanidine and sulfamethazole, trimethoprim, tetracycline, chlortetracycline and tylosin. Linear calibrations were established for all the analytes and the R2 values ranged between 0.9990 and 0.9997. The limits of quantitation (LOQs) varied between 0.025 and 78.8 μg kg-1. The limit of detections (LODs) were better than those that have been reported for the same antibiotics in many instances in other studies and ranged between 0.010-31.5 μg kg-1 with the sulfonamides exhibiting lower sensitivity compared to others. This was attributed to poor response factors, low S/N ratios and matrix interferences. A contrast between the relative responses towards mass spectrometer and ultra-violate/visible (UV/VIS) detection of the analytes is also reported. Sulfonamides exhibited higher response factors towards UV/VIS than mass spectrometer detection and the opposite was true for the rest of the analytes.
Keywords : Quadrupole ion trap; LC-MS; sulfonamides; tetracycline; tylosin; antibiotics; chicken liver; LC-MS/MS.