Tapping technology to advance your ion chromatography methods

Importance of the topic

Objectives and study overview

Instrumental setup

• Reagent-Free Ion Chromatography (RFIC) systems with inline electrolytic eluent generation (KOH/CO3) and continuous suppressor regeneration
• High-efficiency columns: 4 µm hyperbranched polymer packing (e.g. IonPac AS29-Fast-4µm) vs 13 µm baseline columns
• Conductivity detection with suppressed background for low-noise, high-sensitivity measurements
• Optional coupling to single-quadrupole MS via membrane suppressor for haloacetic acids and organic acid analysis

Main results and discussion

• Inorganic anions: reduced eluent consumption by 50% and run times under 8 minutes with enhanced resolution on AS29-Fast-4µm columns; reproducible retention time RSD ≤0.11% in 100 consecutive runs
• Oxyhalides: improved resolution of ethylenediamine carbamate artifacts from fluoride using the AS30 column under a KOH gradient, achieving complete separation within 35 minutes
• Haloacetic acids: IC-ESI-MS/MS method (EPA 557) run time reduced by 39% using AS31 column while maintaining separation of nine HAAs, bromate and dalapon
• Organic acids: IC-MS with AS11-HC-4µm column and single-quad detection for aliphatic and unsaturated acids, with integrated consumables monitoring to automate performance logging
• Trace anions: inline sample neutralization via suppressor regeneration enables direct analysis of caustic solutions; 12-minute runtime for common anions using AS18-4µm
• Amines: CS20 cation exchange column separates alkanolamines and salts in 0.4 µL injections, using methanesulfonic acid gradients for improved selectivity and low noise
• Carbohydrates: dual eluent generation (KOH/MSA) and CarboPac PA200 column deliver high-resolution N-glycan profiling with reproducible gradients on ICS-6000 systems

Benefits and practical applications

• Enhanced chromatographic efficiency and sample throughput with small-particle, high-porosity columns
• Reduced eluent and waste, lower operating costs and simplified workflow via RFIC systems
• Improved detection limits, reproducibility and method flexibility for compliance monitoring and research
• Broad applicability across water analysis, disinfection byproduct screening, pharmaceutical quality control and biopharmaceutical characterization
• Automation and inline sample preparation reduce manual errors and accelerate data acquisition

Future trends and opportunities

• Further miniaturization using microbore formats to increase mass sensitivity and reduce consumable usage
• Tighter integration of IC with high-resolution MS and advanced detectors for multi-analyte profiling
• Artificial intelligence-driven method development for optimized separation and predictive maintenance
• Green chromatography initiatives focusing on water-only eluents and sustainable materials
• Development of novel column chemistries for emerging contaminants and complex biomolecules

Conclusion

References

1. National Primary Drinking Water Regulations. US EPA. https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations
2. Thermo Scientific Application Note AN73607: Inorganic anions in water. 2020.
3. U.S. EPA Hydroxide Eluent Approval Letter. 2002.
4. Thermo Scientific Application Update 73278: Improved separation of EDA carbamate. 2020.
5. U.S. EPA Method 557: Determination of haloacetic acids, bromate and dalapon. 2009.
6. Thermo Scientific Application Note AN73343: Haloacetic acids by IC-MS/MS. 2020.
7. Thermo Scientific Application Note AN73344: Organic acids in pharmaceuticals. 2020.
8. Thermo Scientific Application Note AN72481: Trace anions by auto-neutralization. 2020.
9. Thermo Scientific Application Note 73030: Alkanolamines in neutralizing amines. 2019.
10. Thermo Scientific Application Note 72914: HPAE-PAD glycan profiling. 2019.