An End-To-End Workflow for Quantitative Screening of Multiclass, Multiresidue Veterinary Drugs in Meat Using the Agilent 6470 Triple Quadrupole LC/MS

Significance of the Topic

The emergence of multiclass veterinary drug residues in meat presents a significant food safety concern. Rapid and reliable multiresidue analysis is essential for regulatory compliance, consumer protection and efficient laboratory workflows. The described method streamlines routine screening of over 200 compounds in a range of meat matrices, reducing complexity and increasing throughput.

Objectives and Overview of the Study

This study presents an end-to-end LC/MS/MS workflow for quantitative screening of 210 veterinary drugs in animal muscle tissues intended for human consumption. Using Agilent 6470 and 6495C triple quadrupole instruments, the aim was to develop a single sample-preparation and chromatographic method capable of handling diverse drug classes with consistent performance across chicken, pork and beef matrices.

Methodology and Instrumentation

Sample Preparation

• Solvent extraction of homogenized meat (2 g) using aqueous buffer and acidified organic phases
• Cleanup via Agilent Captiva EMR–Lipid cartridges under positive pressure
• Matrix-matched calibration (0.1–100 µg/kg) and QC spikes at low, medium and high levels

Chromatography

• Agilent 1290 Infinity II LC with InfinityLab Poroshell 120 EC-C18 column
• 13-minute gradient at 0.5 mL/min with ammonium formate/fluoride and formic acid additives

Mass Spectrometry

• Agilent 6470 and 6495C triple quadrupole systems
• Dynamic MRM mode with polarity switching; optimized transitions and collision energies
• Data acquired and processed using Agilent MassHunter software

Main Results and Discussion

Method sensitivity and linearity

• LOD and LOQ met S/N criteria (>3 and >10 respectively) with many analytes below 5 ng/mL
• Calibration curves linear across LOQ to 100 µg/kg (R2 > 0.99 for all targets)

Accuracy and precision

• Average accuracy ranged 73–113%; instrument precision (area %RSD) ≤19%, retention time %RSD ≤0.28%
• Intra-batch repeatability ≤20% RSD; inter-batch reproducibility ≤32% RSD

Recovery and matrix effects

• Recoveries for >97% of compounds within 60–120% range; consistent performance in chicken, pork and beef
• Matrix effects negligible for >93% of targets; minor suppression observed for a small subset

Benefits and Practical Applications

• Single unified workflow replaces multiple class-specific methods
• High throughput 13-min run time; efficient sample cleanup
• Robust performance suitable for routine QA/QC and regulatory labs

Future Trends and Potential Applications

• Expansion to non-targeted and high-resolution screening
• Deeper automation of sample handling and data processing
• Integration with AI-driven spectral libraries and cloud-based analytics

Instrumentation

• Agilent 1290 Infinity II LC with Poroshell 120 EC-C18 column
• Agilent 6470 and 6495C Triple Quadrupole MS with Jet Stream ion source
• Captiva EMR–Lipid SPE cartridges on positive pressure manifold

References

• AOAC Guidelines for Standard Method Performance Requirements, Appendix F, 2016
• US CFR Title 21 Part 556 Tolerances for Veterinary Drug Residues, 2019
• US FSIS Chemical Contaminants of Public Health Concern, 2017
• EU Commission Regulation 37/2010 on Maximum Residue Limits
• AOAC Screening and Identification Method for Regulatory Veterinary Drug Residues, Version 7, 2018