Food contaminant analysis at high resolution mass spectrometry: Application for the determination of veterinary drugs in milk

• Published in: Journal of Chromatography A Vol. 1218; no. 52; pp. 9353 - 9365
• Main Authors: Romero-González, R., Aguilera-Luiz, M.M., Plaza-Bolaños, P., Frenich, A. Garrido, Vidal, J.L. Martínez
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30-12-2011; Elsevier
• Subjects: Animals; Biological and medical sciences; Chromatography, High Pressure Liquid; doxycycline; dried milk; Drug Residues - analysis; Food Analysis - methods; Food industries; Fundamental and applied biological sciences. Psychology; High resolution mass spectrometry; infant formulas; Limit of Detection; livestock; mass spectrometry; Mass Spectrometry - methods; Milk; Milk - chemistry; Milk and cheese industries. Ice creams; monitoring; Orbitrap; Reproducibility of Results; Screening; spiramycin; Time of flight; Ultra-high performance liquid chromatography; ultra-performance liquid chromatography; uncertainty; Veterinary drugs; Veterinary Drugs - analysis; Screening; Veterinary drugs; High resolution mass spectrometry; Time of flight; Orbitrap; Milk; Ultra-high performance liquid chromatography; Ultra performance liquid chromatography; Tandem mass spectrometry; Chemical analysis; Veterinary medicine; Electrospray; Quadrupole spectrometer; Ion trap; chromatography; Food; Quantitative analysis; Drug; Validation; Routine analysis; Contamination; Reversed phase chromatography; Time of flight method; Residue; Ultra-high performance liquid; Comparative study
• ISSN: 0021-9673; 1873-3778
• DOI: 10.1016/j.chroma.2011.10.074

► Determination of veterinary drugs in milk by UHPLC coupled to high resolution mass spectrometry. ► Comparison of two screening/confirmation methods based on Orbtitrap and QqTOF. ► Qualitative validation of screening methods.
Veterinary drugs (VDs) can remain in milk as a consequence of their use in livestock. In order to control the levels of VD residues in milk, screening methodologies can be applied for a rapid discrimination among negative and non-negative samples. In a second stage, non-negative samples are classified as negative or positive samples by using a confirmation method. Pre-target screening methods in low resolution MS (LRMS) are normally applied, but the number of analytes is limited, whereas the information obtained by full scan acquisition in high resolution mass spectrometry (HRMS) is improved. Here, three screening methods (running time
<
4
min) based on Orbitrap, quadrupole-time of flight (QqTOF) and triple quadrupole (QqQ) have been compared, using in all cases ultra-high performance liquid chromatography (UHPLC). For HRMS, the identification of the VDs was based on retention time (RT) and accurate mass measurements. Confirmation was based on the monitoring of fragments generated without precursor selection. The performance characteristics of the screening method provided reliable information regarding the presence or absence of the compounds below an established value, including uncertainty region and cut-off values. Better results in terms of cut-off values (≤5.0
μg
kg
−1, except for spiramycin with a cut-off of 13.4
μg
kg
−1 for milk samples and 43.1
μg
kg
−1 for powdered milk based, emamectin with a cut-off of 42.2
μg
kg
−1 for milk samples and doxycycline, with a cut-off value of 15.8
μg
kg
−1 in powdered milk-based infant formulae) and uncertainty region were obtained using the Orbitrap-based screening method, which was submitted to further validation and used to analyze different real milk samples. The proposed method can be used in routine analysis, providing reliable results.