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Experimental- and simulation-based investigations of coupling a mobile phase gradient with a continuous stationary
Caitlin N Cain1, Anna V Forzano1, Sarah C Rutan1
1Department of Chemistry, Virginia Commonwealth University, 1001 W. Main St., Richmond, VA, 23284-2006, USA.
Journal of Chromatography. A
|June 1, 2019
Summary
This study investigates how stationary phase gradients and column orientation affect chromatography under mobile phase gradients. Optimizing C18 coverage and orientation minimizes peak broadening for better separation.
Area of Science:
- Analytical Chemistry
- Chromatography
Background:
- Continuous stationary phase gradients offer tunable selectivity.
- Understanding ligand effects in gradient columns is crucial for method development.
Purpose of the Study:
- To explore the impact of column orientation and modification degree on gradient stationary phase columns.
- To analyze peak parameters like retention times, widths, and resolution for phenolic compounds.
Main Methods:
- Simulations and experimental fabrication of C18-silica gradient stationary phases.
- Utilizing a mobile phase gradient for chromatographic separation.
- Analysis of peak parameters for five phenolic compounds.
Main Results:
- Simulations indicate peak widths depend on C18 composition and gradient orientation.
- Peak widths minimized on gradient columns with >50% C18 coverage, oriented with dense region at the end.
- Experimental retention times increased on gradient columns, contrasting simulation predictions.
- Specific orientation led to increased retention time and decreased peak width for certain compounds.
Conclusions:
- Combining mobile and stationary phase gradients creates unique ligand interactions.
- Stationary phase gradient orientation significantly influences chromatographic performance.
- Optimized gradient columns can enhance peak focusing and resolution.
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