Veterinary Drug Analysis with Supercritical Fluid Chromatography and Triple Quadrupole LC/MS

Importance of the Topic

Supercritical fluid chromatography combined with triple quadrupole mass spectrometry offers a rapid and highly sensitive approach for detecting trace levels of veterinary drug residues in food and biological matrices. The low viscosity and high diffusion of supercritical CO2 enable fast separations with reduced solvent consumption and improved mass transfer. When coupled to a sensitive electrospray ionization MS source, the technique provides orthogonal selectivity and quantitation capability that support regulatory compliance and food safety monitoring.

Objectives and Study Overview

This study demonstrates the integration of an Agilent 1260 Infinity Analytical SFC system with an Agilent 6490 Triple Quadrupole LC MS instrument for quantifying 18 beta agonists and related veterinary drugs. Key aims include achieving a complete separation within three minutes, establishing method limits of detection and quantitation in the low part per billion range, and evaluating precision, linearity and robustness.

Used Instrumentation

• Agilent 1260 Infinity Analytical SFC Solution with control module binary pump degasser and isocratic pump
• Agilent 6490 Triple Quadrupole LC MS with Jet Stream electrospray source
• Agilent ZORBAX Eclipse Plus Phenyl Hexyl column 2.1 × 150 mm 1.8 micron
• Split flow kit with make up pump for acetonitrile formic acid addition
• MassHunter data acquisition and quantitative software suite

Methodology

Samples were prepared from a veterinary drug test mix and diluted in methanol. The SFC mobile phase comprised CO2 with a methanol modifier ramp from 5 to 20 percent over three minutes. A make up flow of acetonitrile containing formic acid supported electrospray ionization. A capillary restrictor and backpressure regulator maintained 290 bar at 60 deg C. The split configuration delivered part of the flow to the MS and the remainder to waste. Multiple reaction monitoring transitions were optimized for each analyte.

Key Results and Discussion

All 18 compounds were baseline separated in a single minute window within a three minute total run time. Calibration curves from 0.1 to 10 nanograms per milliliter showed linearity coefficients above 0.999. Limits of quantitation were typically below 200 picograms per milliliter with limits of detection down to 17 picograms per milliliter for the most sensitive analytes. Retention time precision was under one percent RSD and peak area precision ranged from five to seventeen percent RSD.

Benefits and Practical Applications

The workflow provides high throughput screening with minimal solvent use and rapid turnaround. It supports residue monitoring in food testing laboratories, quality control in pharmaceutical manufacturing and regulatory compliance for veterinary drug use.

Future Trends and Potential Applications

Advances may include expanded libraries covering hundreds of veterinary compounds, automated method development for novel analytes, coupling with orthogonal detectors for comprehensive profiling and deployment in routine on site testing devices. Integration with data analytics and cloud based reporting will further streamline residue surveillance.

Conclusion

The combined SFC and triple quadrupole MS configuration delivers a robust, fast and sensitive platform for veterinary drug analysis. It achieves low part per billion quantitation limits, excellent precision and high sample throughput, making it suitable for demanding food safety and regulatory applications.

References

• Kempe G Glauner T Spitzbarth F Multi residue screening and confirmation of veterinary drugs in tissue samples by LC MS MS with new triggered MRM acquisition 61st Annual ASMS Conference on Mass Spectrometry and Allied Topics June 2013 Minneapolis MN