A Rapid Screening Method for Sulfa Drugs Using an Advanced UHPLC Column and System

Importance of the Topic

Rapid and reliable screening of sulfonamide antimicrobial residues in food products is critical to protect public health and comply with regulatory limits. Sulfa drugs are commonly used in veterinary medicine and may remain in animal-derived foods. High-throughput methods enable laboratories to detect and monitor these compounds more efficiently and with greater confidence.

Goals and Study Overview

This work demonstrates a fast UHPLC screening method for twelve sulfa drugs using a Thermo Scientific Vanquish UHPLC system coupled with a Hypersil GOLD aQ VANQUISH 1.9 µm column. It highlights the advantages of high-pressure operation, method scaling in Dionex Chromeleon software, and increased flow rates for reducing run times while maintaining chromatographic performance.

Methodology and Instrumentation

A Vanquish UHPLC system was configured with:

• Hypersil GOLD aQ VANQUISH column (1.9 µm, 100 × 2.1 mm)
• Binary Pump H and Split Sampler HT
• Column Compartment H with Active Pre-heater (55 °C)
• Diode Array Detector HL (LightPipe flow cell, 10 mm, detection at 260 nm)
• Thermo Scientific Virtuoso Vial Identification System

Mobile phases were 0.1% formic acid in water (A) and 0.1% formic acid in acetonitrile (B). A 1 µL injection volume and flow rates of 0.5, 1.0, or 1.6 mL/min were evaluated. Sample solutions of twelve sulfonamides were prepared at 100 µg/mL in water/methanol (1:1 or 3:7) and accommodated using 2 mL screw-thread vials.

Main Results and Discussion

At 0.5 mL/min (440 bar), full separation of all twelve sulfa drugs was achieved in under seven minutes. By exploiting the Vanquish system’s 1500 bar capability, the flow rate was increased to 1.6 mL/min without loss of baseline resolution (resolution ≥ 1.5 for all critical pairs), reducing total run time to approximately two minutes (backpressure ~ 1376 bar).

Benefits and Practical Applications

This rapid UHPLC method offers:

• High throughput screening of veterinary sulfonamides in food matrices
• Baseline resolution of structurally similar compounds
• Short run times (< 2.1 minutes) for increased sample throughput
• Simple method scaling using Chromeleon software’s built-in calculator to adjust flow rate and column dimensions

Future Trends and Opportunities

Continued advances in column chemistry and UHPLC hardware will push flow rates and pressures even higher, further shortening analysis times. Integration with mass spectrometry detection could expand specificity and sensitivity for residue confirmation. Automated sample preparation and data processing tools are likely to enhance laboratory efficiency and data integrity.

Conclusion

The combination of Hypersil GOLD aQ VANQUISH columns and the Vanquish UHPLC system delivers a robust, high-speed screening method for sulfa drugs. High-pressure operation and intuitive method scaling allow significant reduction in analysis time without sacrificing chromatographic performance, making this approach well suited to routine QA/QC and regulatory laboratories.