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Post Column Derivatization Using Reaction Flow High Performance Liquid Chromatography Columns
Published on: April 26, 2016
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On the performance of conically shaped columns: Theory and practice
Fabrice Gritti1, Jon Belanger1, Gary Izzo1
1Waters Corporation, 34 Maple Street, Milford, MA 01757, USA.
Journal of Chromatography. A
|February 2, 2019
Summary
Conical chromatography columns show slightly lower efficiency but offer reduced peak tailing and improved peak capacity in gradient elution, especially when flow is from wide to narrow ends. This technology is promising for ultra-fast separations.
Area of Science:
- Analytical Chemistry
- Chromatography
- Separation Science
Background:
- Conventional cylindrical columns are standard in chromatography.
- Investigating novel column geometries is crucial for enhancing separation performance.
- Conical columns present a unique geometry with potential chromatographic benefits.
Purpose of the Study:
- To evaluate the chromatographic performance of conical columns compared to conventional ones.
- To investigate the impact of flow direction on conical column efficiency and peak capacity.
- To assess the suitability of conical columns for ultra-fast gradient separations.
Main Methods:
- Experimental preparation and packing of a conical column with 5 μm XBridge-C18 particles.
- Comparative chromatographic analysis against a standard cylindrical column.
- Application of Giddings' and Blumberg's theories for fundamental understanding.
Main Results:
- Conical columns exhibited 15% lower efficiency than conventional columns, irrespective of flow direction.
- Blumberg's theory predicted marginal outperformance for conical columns in gradient elution under specific outlet-to-inlet i.d. ratios.
- Flow from wide to narrow end improved peak capacity by 11.0% for small molecules and 8.5% for peptides, reducing losses.
- Conical columns demonstrated reduced peak tailing and minimized sample dispersion.
Conclusions:
- Conical columns offer advantages in reduced peak tailing and suitability for ultra-fast gradient separations.
- Optimizing flow direction (wide to narrow) is key to maximizing peak capacity in conical columns.
- While slightly less efficient, conical columns present a viable alternative for specific high-speed chromatographic applications.
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