- Acknowledgements: DMG thanks the “Ministerio de Economía y Competitividad” for a Juan de la Cierva postdoctoral research contract (ref. FJCI-2014-19573).
- Authors: A. Grande-Martínez, D. Moreno-González, F.J. Arrebola-Liébanas, A. Garrido-Frenich, A.M. García-Campaña.
- Reference: Journal of Pharmaceutical and Biomedical Analysis 155 (2018) 27–32.
In this work a sample treatment based on a modified QuEChERS method combined with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was proposed to determine the residues of five common tetracyclines in fish muscle samples. The separation was achieved in less than 4 min and the analytes were detected in electrospray ionization in positive mode (ESI+) with multiple reaction monitoring mode. Parameters affecting the extraction step, such as the amount of sample and EDTA-McIlvaine buffer and extraction solvent volumes, were optimized by means of experimental design. In order to obtain the lowest matrix effect, parameters affecting the clean-up step by dispersive solid phase extraction (dSPE), were also studied. Under optimum conditions, matrix effect was lower than │15│% in all cases. Limits of quantification were lower than 4.4 μg kg−1 for the compounds in the selected samples, being in compliance with the current legislation. The precision, expressed as relative standard deviation, was below 18.5% and the recoveries for fortified fish samples (salmon and panga) higher than 80%. These results revealed that the proposed method is simple, rapid, cheap and environmentally friendly, being successfully applicable for the determination of these residues in fish samples.
