Agilent Hi-Plex Columns for Carbohydrates, Alcohols, and Acids

Importance of the Topic

Separation of carbohydrates, sugar alcohols and organic acids is critical in quality control of food and pharmaceutical products.
Agilent Hi-Plex columns combine ion-exchange and ligand-exchange mechanisms to enable efficient, isocratic HPLC analyses using water or dilute acids, reducing solvent hazards and system complexity.

Objectives and Study Overview

This study demonstrates the performance of Hi-Plex columns with different counter ions and crosslinking densities for the analysis of simple sugars, oligosaccharides, sugar alcohols, and organic acids under isocratic conditions.

Methodology and Instrumentation

• Columns studied: Hi-Plex H (8% crosslinked, H+ form), Hi-Plex Ca (4% crosslinked, Ca2+ form), Hi-Plex Ca (Duo) (8% crosslinked, Ca2+).
• Eluents: 100% water or dilute sulfuric acid (0.0085–0.1 M).
• Flow rates: 0.4–0.6 mL/min; temperatures: 50–85 °C.
• Detectors: refractive index (RI) and UV at 210 nm.
• Instrumentation: Agilent HPLC system equipped with appropriate column oven and detectors.

Main Results and Discussion

• Hi-Plex H achieved baseline separation of nine organic acids with plate counts up to ~22,000 and asymmetry factors near unity.
• Monosaccharides and glycerol were resolved in under 30 minutes using RI detection at 65 °C.
• Hi-Plex Ca efficiently separated common sugars and sugar alcohols at 85 °C, with resolution of raffinose, sucrose, lactulose, glucose, and sorbitol.
• Hi-Plex Ca (Duo) provided improved selectivity for mono‐ and oligosaccharides, handling larger oligomers with satisfactory efficiency.

Practical Benefits and Applications

• Isocratic operation with aqueous eluents enhances robustness and simplifies maintenance.
• High resolution and reproducibility support routine QA/QC in food and pharmaceutical laboratories.
• Reduced solvent use lowers operating costs and environmental impact.

Future Trends and Potential Applications

• Integration with mass spectrometry for structural elucidation of complex carbohydrates.
• Development of miniaturized and automated HPLC systems for high‐throughput analysis.
• Expansion of stationary phase chemistries to target novel bioactive oligosaccharides and glycan profiling.

Conclusion

Agilent Hi-Plex columns offer versatile, high-performance solutions for isocratic separation of carbohydrates, sugar alcohols, and organic acids under aqueous conditions, meeting industry requirements for efficiency, selectivity, and sustainability.

References

• Agilent Technologies. Agilent Hi-Plex Columns for Carbohydrates, Alcohols, and Acids. Application Note 5990-8264EN, 2011.