Determination of Antibiotics Residues in Milk Using a QuEChERS Method Using Full Factorial Design and Liquid Chromatography-Tandem Mass Spectrometry

Abstract

This study evaluated different methods of extraction based on quick, easy, cheap, effective, rugged and safe (QuEChERS) method for analysis of the antibiotics ceftiofur, cloxacillin and enrofloxacin in milk using ultra-performance liquid chromatography-tandem mass spectrometry. The QuEChERS acetate method has been shown to be inefficient for extracting such antibiotics. The optimized QuEChERS method presented excellent recoveries, from 95 to 99%. A complete factorial design was used to evaluate the effects of variables of the clean-up step: anhydrous octadecylsilane (C18), primary secondary amine (PSA) and sodium acetate (NaAc). Linearity (R 2) above 0.96 was achieved for all compounds. Accuracy and precision were assessed by recovery. Accuracy was 91-99%. Intraday precision with relative standard deviations (RSD) lower than 12.3% and interday precision lower than 12.4% were obtained. Limits of detection (LOD) and quantification (LOQ) were obtained between 1.4-6.8 and 1.5-8.7 µg L-1 , respectively. The applicability was evaluated using 91 real milk samples.

FTIR spectroscopy with chemometrics for determination of tylosin residues in milk

“…The screening tests are nonspecific, while the chromatographs are specific and quantify the substance; however, they are laborious, use many chemical reagents, require trained personnel and their analytical speed is low 2,36 . Even with studies to increase their analytical efficiency, 37–39 chromatographic techniques continue to use noxious reagents, requiring time and trained personnel. For the offer of safe food, it is essential that the number of samples evaluated increases, which implies the search for other techniques and methodologies.…”

Effects of Different Processing Methods on the Antibiotic Enrofloxacin Residues Occurrence in Middle Eastern Dairy Products. (c2020)

“…The modified QuEChERS has shown that it is very efficient for detecting enrofloxacin residues in the milk and cheese. It has been used in many studies, the most recent of which is a study published by Grabsk et al (2019), and aimed at determining several antibiotics residues, including enrofloxacin in milk and dairy, through the modified QuEChERS method, Full Factorial Design and Liquid Chromatography-Tandem Mass Spectrometry (Grabsk et al, 2019).…”

“…After that, the extraction salts, QuEChERS salt, were added to the tube then shacked again by hand for 10 minutes, then centrifuged for 5 min at 5000 rpm at 4 o C. After the centrifuge was done, 5 ml of the upper layer of the polypropylene centrifuged tube were removed using a pipette and added to a dispersive EMR tube previously activated with 5 ml water, after which the latter tube undergone shaking by hand for 3 mins, followed by centrifugation for 5 min at 5000 rpm at 4 o C. Once the centrifugation was performed, 5 ml were removed from the upper layer of the polypropylene centrifuged tube and added to the polish tube, and got mixed by shaking for 1min, and then put in the polypropylene centrifuge again for 5 min at 14000 rpm at 4 o C. Lastly, the resultant liquid was filtered with pvdf of pore size 0.22 micron, to remove any residual lumps. This step is considered as a cleaning step for the extraction (Grabsk et al, 2019). After extracting the enrofloxacin residues from the cheese or milk samples, the vial containing the residues was placed in the Liquid Chromatography-Mass Spectrometry LC-MS (SCHIMADZU LCMS-8045)…”