Determination of Benzimidazole Residues in Animal Tissue by Ultra High Performance Liquid Chromatography Tandem Mass Spectrometry

Importance of the Topic

Benzimidazoles are widely used anthelmintics in veterinary medicine. Their residues and metabolites can present teratogenic or mutagenic hazards, making sensitive and reliable monitoring in animal tissues essential for food safety, regulatory compliance, and consumer protection.

Objectives and Study Overview

The aim was to develop and validate a rapid UHPLC-ESI-MS/MS method for simultaneous determination of 16 benzimidazole compounds and metabolites in animal tissue. Key goals included achieving low detection limits, high throughput, and robust performance to meet veterinary drug residue analysis requirements.

Methodology and Instrumentation

Sample preparation involved alkaline extraction with ethyl acetate–50% KOH and BHT, n-hexane defatting, and cleanup via MCX SPE cartridges.

• Chromatography: Shimadzu Nexera UHPLC system with Shim-pack XR-ODS III column (2.0×50 mm, 1.6 µm) at 30 °C; mobile phases of 0.1% formic acid in water (A) and acetonitrile (B); gradient elution at 0.4 mL/min; 20 µL injection.
• Mass Spectrometry: Shimadzu LCMS-8040 triple quadrupole with electrospray ionization in positive MRM mode; ionization voltage +4.5 kV; nebulizing gas 3.0 L/min; DL temperature 200 °C; heat block 350 °C.

Main Results and Discussion

Calibration curves for all analytes were linear over 0.5–50 ng/mL with correlation coefficients (R²) between 0.9993 and 0.9999. Method repeatability (%RSD) for retention time and peak area was below 5% at 0.5, 5, and 50 ng/mL. Limits of detection ranged from 1.0 to 2.2 µg/kg. Recovery experiments in pork spiked at 10 µg/kg produced 80.9–118.5% recoveries with RSDs under 5%, confirming accuracy and precision.

Benefits and Practical Applications

This validated method offers high throughput with a six-minute run time, sensitive detection of multiple benzimidazoles at trace levels, and reliable quantification suitable for routine screening in veterinary drug residue monitoring and quality control laboratories.

Future Trends and Applications

Potential developments include integration with high-resolution MS for metabolite identification, automation of sample preparation to boost throughput, and expansion to multi-class residue analysis covering additional veterinary pharmaceuticals.

Conclusion

A streamlined UHPLC-ESI-MS/MS workflow was established for accurate, sensitive, and reproducible determination of 16 benzimidazole residues in animal tissues, supporting regulatory monitoring and food safety assurance.

Reference

No formal literature references were provided in the source document.