Analysis of 122 Veterinary Drugs in Meat Using All Ions MS/MS with and Agilent 1290/6545 UHPLC-Q-TOF System

Significance of the Topic

Monitoring veterinary drug residues in meat is critical to safeguard consumer health and manage antimicrobial resistance. A reliable, rapid method that can detect hundreds of compounds across diverse chemical classes enhances food safety oversight and supports regulatory compliance.

Aims and Study Overview

This work aimed to establish a 12-minute, single-run analytical protocol for 122 priority veterinary drugs in bovine liver, kidney, and muscle. The approach leverages high-resolution All Ions MS/MS on an Agilent UHPLC-Q-TOF, coupled with a veterinary drugs spectral library, to simultaneously screen and quantify residues at nanogram per gram levels relative to maximum tolerance limits.

Methodology and Used Instrumentation

Sample preparation employed QuEChERS Enhanced Matrix Removal-Lipid cleanup from 2 g tissue spikes at 0.5×, 1×, and 2× tolerance levels. Chromatographic separation used an Agilent 1290 Infinity UHPLC system with a ZORBAX Eclipse Plus C18 column (2.1×150 mm, 1.8 μm), gradient elution (water/MeCN with 0.1% formic acid) at 0.5 mL/min, 30 °C, 15 μL injection.

The Agilent 6545 Q-TOF, equipped with a Jet Stream ESI source, acquired data in simultaneous 0, 10, and 40 eV collision energy channels across m/z 50–1000. Reference masses and SWARM fragile-ion tuning ensured mass accuracy. Data were processed in MassHunter Qualitative using the Find by Formula workflow against the Agilent Veterinary Drugs PCDL, applying stringent mass (±10 ppm), retention time (±0.2 min), isotope, and fragment ion coelution criteria.

Main Results and Discussion

Over 92% of target compounds were detected in all matrices at each spike level, with positive identifications (precursor, fragment, RT match) for 79–90%. False positives were mitigated by requiring coeluting fragments and library-matched retention times. For example, novobiocin and enrofloxacin were conclusively identified via accurate mass, MS/MS fragments, and coelution scoring. Nine analytes (e.g., certain β-lactams) were not detected, likely due to degradation; with fresher standards, these were later recoverable.

Calibration experiments in ground beef and liver across 2–100 ng/g yielded linear responses (R2>0.99 for >85% of analytes) without internal standard correction, demonstrating the method’s quantitative capability.

Benefits and Practical Applications

The described protocol allows high-throughput screening and quantification of multiclass veterinary residues in a single 12-minute run, reducing false positives and negating repeated standard injections. Its flexibility supports retrospective data mining for emerging contaminants and streamlines compliance testing in food safety laboratories.

Future Trends and Possibilities

Advancements may include expanding spectral libraries to new drugs and metabolites, integrating automated AI-driven data evaluation, and adapting the workflow to other food matrices or environmental samples. The All Ions MS/MS strategy can further facilitate non-targeted surveillance and retrospective analysis without re-acquisition.

Conclusion

An Agilent 1290/6545 UHPLC-Q-TOF method with All Ions MS/MS and a spectral library enables rapid, reliable detection and quantification of 122 veterinary drugs in meat. The approach meets regulatory requirements for sensitivity and specificity, offering a robust tool for routine screening and risk assessment.

References

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