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Curtain Flow Column: Optimization of Efficiency and Sensitivity
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Study of the column efficiency using gradient elution based on Van Deemter plots.

T Alvarez-Segura1, E Cabo-Calvet1, J J Baeza-Baeza1

  • 1Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, 46100 Burjassot, Spain.

Journal of Chromatography. A
|December 1, 2018
PubMed
Summary

This study introduces a new method to measure chromatographic column efficiency during gradient elution by keeping the mean retention factor constant. This approach allows for more reliable comparisons with isocratic elution, revealing that gradient elution can achieve similar resolution under specific conditions.

Keywords:
Column characterizationData treatmentDispersion parametersLiquid chromatographyPeak profileVan Deemter plots

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Area of Science:

  • Analytical Chemistry
  • Chromatography Science

Background:

  • Column performance is crucial for efficient separation methods.
  • Traditional efficiency measurements rely on isocratic elution and the Van Deemter equation.
  • Gradient elution efficiency measurement presents unique challenges due to changing retention factors.

Purpose of the Study:

  • To develop and validate an approach for measuring column efficiency in linear gradient elution.
  • To maintain a constant mean retention factor during gradient elution for consistent comparisons.
  • To compare gradient elution efficiency with isocratic elution under controlled conditions.

Main Methods:

  • Applied a novel approach to measure efficiency in linear gradient elution by fixing the mean retention factor.
  • Utilized Zorbax Eclipse XDB C18 and Chromolith SpeedROD C18 columns with sulphonamide probe compounds.
  • Compared results with isocratic elution and gradient elution with a constant gradient program.

Main Results:

  • Experimentally obtained mean compression factors were higher than predicted for both columns.
  • Column efficiencies improved at lower flow rates and higher gradient slopes.
  • Similar resolution was observed between isocratic and gradient elution when the mean retention factor was constant.

Conclusions:

  • The proposed method allows for meaningful efficiency comparisons between isocratic and gradient elution.
  • Gradient elution can provide comparable resolution to isocratic elution under optimized conditions.
  • Flow rate and gradient slope significantly impact chromatographic efficiency and resolution in gradient elution.