Determination of Aromatic Amines Derived from Azo Colorants by GC/MS Using Supported Liquid Extraction Chem Elut S Cartridges

Significance of the Topic

Aromatic amines released from the reductive breakdown of azo dyes pose significant health and environmental risks, including carcinogenicity. Accurate quantification of these compounds in textiles and related products is essential for compliance with regulations such as ISO 14362-1 and for ensuring consumer safety.

Objectives and Study Overview

This application note evaluates Agilent Chem Elut S supported liquid extraction cartridges for the quantitative determination of aromatic amines derived from azo colorants. The study aims to assess recovery, precision, and workflow efficiency for three cartridge formats at a target concentration of 30 µg/mL using GC/MS in selected ion monitoring mode.

Methodology and Instrumentation

The sample preparation follows a simulated ISO 14362-1 protocol, where azo dyes are first reduced to aromatic amines in a citrate buffer with sodium dithionite. Key steps include

• Loading 5, 10 or 20 mL aqueous sample onto Chem Elut S cartridges under gravity
• Holding the sample on the synthetic extraction medium for 15 minutes
• Eluting analytes with methyl tert-butyl ether (MTBE)
• Direct injection of 1 µL extract into GC/MS

Instrumentation details

• GC system Agilent 7890
• MS detector Agilent 5977 GC/MSD in SIM mode
• Column Agilent J&W DB-35ms 30 m × 250 µm × 0.25 µm
• Oven program 100 °C initial, ramp at 10 °C/min to 320 °C

Main Results and Discussion

All three cartridge formats delivered high recoveries ranging from 87 to 119 % across 20 target amines, with relative standard deviations below 9 %. The 10 mL, 60 cc format showed particularly consistent performance. Extending the hold time to 15 minutes improved extraction efficiency by up to 38 % for certain analytes. The synthetic Chem Elut S medium demonstrated uniform packing, optimal flow, and excellent matrix removal compared to traditional diatomaceous earth sorbents.

Benefits and Practical Applications

• Time savings through gravity-driven sample loading and elution
• High reproducibility and batch-to-batch consistency
• Simplified workflow with minimal post-treatment
• Compliance with European regulations on azo dye analysis

Future Trends and Opportunities

Advancements may include integration of automated sample handling, expansion to other polar analytes, miniaturized cartridge designs, and adoption of greener solvents. Coupling with high-resolution MS and in-line derivatization could further enhance sensitivity and selectivity.

Conclusion

Agilent Chem Elut S cartridges provide a robust, efficient, and reproducible sample preparation method for GC/MS analysis of carcinogenic aromatic amines from azo dyes. The high recoveries, low RSD values, and streamlined workflow support routine compliance testing and research applications.

References

• Freeman HS Aromatic amines Use in Azo Dye Chemistry Front Biosci Landmark Ed 2013 18 145 164
• Pielesz A et al Detection and Determination of Aromatic Amines as Products of Reductive Splitting from Selected Azo Dyes Ecotoxicol Environ Saf 2002 53 1 42 47
• ISO 14362-1 Textiles Methods for Determination of Certain Aromatic Amines Derived from Azo Colorants Part 1 Detection of the Use of Certain Azo Colorants Accessible with and Without Extracting the Fibres EN 14362-1 2012