Online fully automated SPE‐HPLC‐MS/MS determination of ceftiofur in bovine milk samples employing a silica‐anchored ionic liquid as sorbent

• Published in: Electrophoresis 2018-09, Vol.39 (17), p.2210-2217
• Main Authors: Ferreira, Débora Cecatto, Toffoli, Ana Lúcia, Maciel, Edvaldo Vasconcelos Soares, Lanças, Fernando Mauro
• Format: Article
• Language: English
• Subjects: Animals; Antibiotics; Cattle; Ceftiofur; Cephalosporins - analysis; Cephalosporins - isolation & purification; Chromatography, High Pressure Liquid - methods; Correlation coefficients; Drug Residues - analysis; Drug Residues - isolation & purification; Flow velocity; Fourier transforms; High performance liquid chromatography; Ionic liquid; Ionic liquids; Ionic Liquids - chemistry; Ions; Limit of Detection; Linear Models; Linearity; Low concentrations; Mass spectrometry; Milk; Milk - chemistry; Milk analysis; On-line systems; Online SPE; Reproducibility; Reproducibility of Results; Residues; Scanning electron microscopy; Silicon dioxide; Silicon Dioxide - chemistry; Solid Phase Extraction - methods; Tandem Mass Spectrometry - methods
• ISSN: 0173-0835; 1522-2683
• DOI: 10.1002/elps.201800053

Solid‐phase extraction coupled online with high performance liquid chromatography and tandem mass spectrometry was successfully applied to determine low concentrations of ceftiofur antibiotic in bovine milk samples. A silica‐anchored ionic liquid was applied as sorbent material to be used as extraction phase in the proposed online system. The material was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. In order to improve the system reproducibility, the following experimental parameters were optimized: organic solvent percentage, time and sample loading flow rate. Subsequently, the method was validated presenting satisfactory results as adequate selectivity, good linearity and correlation coefficient higher than 0.98. The limit of detection and quantification were 0.1 and 0.7 μg/L, respectively. The precision of the methodology was evaluated as repeatability and intermediate precision, with relative standard deviation values lower than 15%. The accuracy of the method ranged from 72.8 to 137% and the minimum and maximum recovery values were 73.4 and 111.3%, respectively. After the validation, seven milk samples were analyzed and although ceftiofur was not detected in any of them the method was demonstrated to be efficient when applied to the analysis of milk samples fortified with the pollutant of interest.