The Analysis of Veterinary Drug Residues in Animal Muscle Tissue Using Multi-Residue Screening Based Upon Liquid Chromatography-Tandem Quadrupole Mass Spectrometry

Significance of the Topic

Ensuring the safety of animal-derived food products requires robust methods to detect veterinary drug residues in muscle tissues. Residues from antibiotics, antiparasitics and other drug classes must be monitored to comply with regulatory limits and protect public health.

Objectives and Study Overview

This work aimed to consolidate the detection of over 150 veterinary drugs into a single multi-residue screening method using UPLC-MS/MS. The study validated performance in muscle samples against EU guidelines and established screening target concentrations (STCs) below maximum residue limits (MRLs).

Methodology and Instrumentation

Samples of minced muscle tissue from various species were extracted using a generic acidic acetonitrile liquid–liquid extraction with oxalic acid to enhance recovery of chelating compounds, followed by dispersive solid-phase extraction clean-up to remove lipids and phospholipids.
Instrumental Setup:

• Chromatography: ACQUITY UPLC I-Class PLUS with HSS T3 column (1.8 μm, 2.1×100 mm) at 40 °C, gradient elution in 15 min.
• Mass spectrometry: Xevo TQ-XS operated in electrospray with polarity switching, capillary voltage ESI+ 1.0 kV, ESI– 2.5 kV, desolvation at 600 °C.
• Software: MassLynx v4.2 and TargetLynx XS for data acquisition and processing.

Main Results and Discussion

Validation followed the Commission Decision 2002/657/EC screening protocol. Blank and spiked samples at 0.1, 1.0 and 10 μg/kg determined Threshold (T) and Cut-off factor (Fm) to establish detection capability (CCβ). Of 158 tested analytes, 152 achieved CCβ at or below 1.0 μg/kg, with nearly 70% at 0.1 μg/kg, all below relevant MRLs or reference concentrations.

Benefits and Practical Applications

• Simultaneous screening of multiple drug classes in a single run improves laboratory throughput and cost efficiency.
• Generic extraction and dSPE clean-up reduce sample preparation time and instrument maintenance.
• Validated performance provides confidence for routine regulatory and industry monitoring.

Future Trends and Potential Uses

• Extension of the workflow to other food matrices such as milk, eggs and seafood.
• Incorporation of high-resolution mass spectrometry for non-targeted screening of emerging contaminants.
• Automation and miniaturized sample preparation to further increase throughput and reproducibility.

Conclusion

The presented UPLC-MS/MS multi-residue screening method is sensitive, robust and fit for routine monitoring of veterinary drug residues in muscle tissues, achieving detection limits well below regulatory thresholds.

References

1. Commission Decision 2002/657/EC: Implementing Council Directive 96/23/EC. Off. J. Eur. Commun. 2002;221:8.
2. CRL Guidance Paper, 7 Dec 2007. State of the Art Analytical Methods for National Residue Control Plans.
3. EFSA. Report on Veterinary Medicinal Product Residues in Live Animals and Animal Products 2018. EFSA Suppl. Publ. 2020;EN-1775.
4. Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines. CRLs 20/1/2010.
5. Young M, Van Tran K, Goh E, Shia J. UPLC-MS/MS Determination of Aminoglycoside Antibiotics in Meat and Milk. Waters App Note 720004512en. 2012.