Increase Productivity for Dioxin and Furan Analysis With Rtx®-Dioxin2 GC Columns

Significance of Dioxin and Furan Analysis

Polychlorinated dibenzo-dioxins (PCDDs) and dibenzofurans (PCDFs) are highly toxic environmental pollutants that require accurate quantification at trace levels. The separation of critical isomers such as 2,3,7,8-TCDD and 2,3,7,8-TCDF presents analytical challenges even when using high-resolution mass spectrometry. Improved chromatographic phases with high thermal stability and selectivity are essential to enhance laboratory productivity, reduce analysis time, and ensure reliable data for regulatory compliance and environmental monitoring.

Objectives and Study Overview

This application note evaluates the performance of the Rtx®-Dioxin2 GC column for the analysis of PCDD and PCDF congeners. Key goals include demonstrating isomer specificity for 2,3,7,8-substituted congeners, exploiting the column’s 340 °C thermal limit to shorten run times, and assessing the impact on throughput and instrument utilization in a routine high-resolution mass spectrometry (HRMS) laboratory.

Methodology and Instrumentation

Sample and Column

• Test mixture of PCDD/PCDF congeners prepared in the laboratory
• Rtx®-Dioxin2, 60 m × 0.25 mm ID, 0.25 µm film thickness (Restek cat.# 10758)

GC-HRMS Conditions

• GC System: Agilent/HP 6890
• Injection: 1 µL splitless, inlet 290 °C
• Carrier Gas: He at 1.5–1.7 mL/min constant flow
• Oven Programs:
   • TCDD Analysis: 150 °C (1 min) → 210 °C at 30 °C/min (1 min) → 250 °C at 3 °C/min (12 min) → 330 °C at 70 °C/min (6 min)
   • TCDF Analysis: 180 °C (1 min) → 235 °C at 45 °C/min (1 min) → 250 °C at 3 °C/min (15 min) → 300 °C at 50 °C/min (1 min)
• Detector: Micromass Autospec Ultima HRMS (magnetic sector, EI, PFK tune)
• Transfer Line and Source: 290 °C

Main Results and Discussion

• Isomer specificity: Baseline separation of all tetrachloro-dioxin and furan isomers including critical 2,3,7,8-congeners was achieved on a single column.
• Thermal stability: The Rtx®-Dioxin2 phase tolerates up to 340 °C, which enabled faster temperature ramps and reduced cycle times by 40% for the EPA 1613 TCDD-only method.
• Low bleed and extended lifetime: High temperature operation minimized column bleed, preserving resolution and extending column life compared to cyano-based confirmation phases.
• Improved throughput: Maxxam Analytics reported a reduction in run time from 50 to 30 minutes for TCDD-only analyses, saving 20 minutes per sample and allowing consolidation of TCDD and TCDF confirmations on one instrument.

Benefits and Practical Applications

• Increased sample throughput and instrument capacity for full-list PCDD/PCDF and PCB analyses.
• Reduced instrument downtime and fewer column changes lower operating costs.
• Enhanced accuracy and reproducibility by eliminating coelution interferences and simplifying resolution checks.
• Lower detection limits and less carryover due to high thermal stability and efficient high-temperature cleaning.

Future Trends and Potential Uses

The development of robust high-temperature stationary phases like Rtx®-Dioxin2 is expected to drive further integration with automated HRMS workflows and multi-analyte environmental testing. Prospective advances include miniaturized column formats for faster screening, coupling with tandem mass spectrometry for enhanced selectivity, and broader application in food safety, soil monitoring, and regulatory compliance labs.

Conclusion

The Rtx®-Dioxin2 GC column offers exceptional isomer selectivity, high thermal resilience, and significant reductions in analysis time for dioxin and furan determinations. Its adoption can streamline HRMS-based workflows, improve laboratory productivity, and support precise trace-level quantification required by regulatory methods such as EPA 1613.

Reference

• EPA Method 1613: Tetra- through Octa-Chlorinated Dioxins and Furans by Isotope Dilution HRGC/HRMS
• Restek Corporation Lit. Cat.# GNTS1511-UNV, 2012