Waters Cortecs 1.6 μm columns

Significance of the Topic

Solid-core sub-2-µm columns represent a major advancement in ultra-performance liquid chromatography by reducing eddy diffusion, axial dispersion, and mass transfer resistance. This innovation enables higher efficiency, improved resolution, and greater throughput compared to fully-porous and larger particle formats, meeting the growing demands of modern analytical workflows.

Study Objectives and Overview

This white paper introduces Waters CORTECS UPLC 1.6 µm columns and evaluates their performance relative to fully-porous 1.7 µm and competitor solid-core columns. Goals include quantifying efficiency gains, resolution improvements, throughput enhancements, and batch-to-batch reproducibility across three chemistries: C18+, C18, and HILIC.

Methodology and Instrumentation

Comparative separations were conducted under isocratic and gradient conditions on ACQUITY UPLC systems and mass spectrometers to assess column performance. Key instrumentation used:

• ACQUITY UPLC I-Class and H-Class systems with ultra-low dispersion hardware
• ACQUITY PDA detector for UV analysis
• Xevo TQ-S and Xevo TQD mass spectrometers for MS/MS detection

Columns of various dimensions (2.1×30–150 mm and 3.0×30–150 mm) were evaluated at flow rates from 0.5 to 1.0 mL/min, temperatures up to 45 °C, and using water, acetonitrile, ammonium formate, and formic acid mobile phases.

Key Results and Discussion

• Efficiency: CORTECS C18+ achieved up to 39 % higher plate counts than competitor 1.7 µm solid-core columns at optimal flow.
• Resolution: USP resolution more than doubled for local anesthetics on HILIC pillars versus fully-porous formats.
• Throughput: Doubling flow rates maintained or increased peak capacity, cutting run times in half without loss of separation quality.
• Reproducibility: Four production batches of CORTECS C18 showed minimal retention and efficiency variance, ensuring method reliability.
• Selectivity: Three phase chemistries deliver versatile retention: C18+ for basic analytes with improved peak shape, C18 for balanced reversed-phase separations, and HILIC for polar compound retention and MS sensitivity.

Benefits and Practical Applications

• Higher throughput with maintained resolution reduces analysis time and solvent usage.
• Scalability across different system dispersions and column formats streamlines method transfer between HPLC and UPLC.
• Improved peak shape for basic compounds eliminates the need for ion-pair reagents in many workflows.
• Applications span pharmaceutical impurity profiling, bioanalysis, metabolomics, forensic toxicology, and environmental testing.

Future Trends and Opportunities

Ongoing developments in low-dispersion UHPLC hardware and next-generation particle chemistries will further leverage the advantages of sub-2-µm solid-core columns. Charged surface modifications and miniaturized high-throughput formats are poised to expand capabilities in automated screening, clinical diagnostics, and regulatory compliance.

Conclusion

CORTECS UPLC 1.6 µm columns fulfill the promise of solid-core technology by delivering exceptional efficiency, resolution, reproducibility, and method flexibility. Their integration with advanced UPLC systems empowers laboratories to achieve faster, more sensitive, and more robust separations.

References

• Guiochon G, Gritti F. Mechanisms of efficiency gain with solid-core particles. J Chromatogr A. 2011;1218:1915–1938.