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Post Column Derivatization Using Reaction Flow High Performance Liquid Chromatography Columns
Published on: April 26, 2016
Fitting adsorption isotherms to the distribution data determined using packed micro-columns for high-performance
P Jandera1, S Bunceková, K Mihlbachler
1Department of Analytical Chemistry, University of Pardubice, Czech Republic. pavel.jandera@upce.cz
Journal of Chromatography. A
|August 25, 2001
Summary
Determining adsorption isotherms using micro-bore and capillary high-performance liquid chromatography (HPLC) columns significantly reduces the need for expensive pure compounds. This method offers a cost-effective alternative for optimizing preparative separations.
Area of Science:
- Analytical Chemistry
- Chromatography
- Separation Science
Background:
- Adsorption isotherms are crucial for understanding and optimizing preparative high-performance liquid chromatography (HPLC) separations.
- Conventional methods for determining adsorption isotherms, such as frontal analysis on analytical columns, require substantial amounts of pure compounds, leading to high costs, particularly for enantiomers.
Purpose of the Study:
- To investigate the feasibility of using packed micro-bore and capillary HPLC columns for determining adsorption isotherms.
- To assess the cost-effectiveness and compound consumption reduction offered by smaller column formats.
Main Methods:
- Adsorption isotherms were determined using frontal analysis and perturbation techniques on micro-bore (1 mm I.D.) and capillary (0.32 mm I.D.) HPLC columns.
- Model compounds (benzophenone, o-cresol, phenol) in reversed-phase systems and enantiomers of mandelic acid on a chiral stationary phase were studied.
- Results were compared with those obtained from conventional analytical columns (3.3 mm I.D.).
Main Results:
- A good agreement was observed between isotherm coefficients determined on micro-columns and conventional columns packed with the same material.
- The consumption of pure compounds decreased significantly with smaller column inner diameters: 10-fold for micro-bore and 100-fold for capillary columns compared to conventional columns.
- Both frontal analysis and perturbation techniques proved suitable for isotherm determination on micro-columns.
Conclusions:
- Micro-bore and capillary HPLC columns are effective tools for determining adsorption isotherms.
- Utilizing smaller column formats drastically reduces the quantity of pure compounds required, offering a more economical approach for preparative HPLC optimization.
- This methodology enhances the efficiency and reduces the cost associated with characterizing chromatographic systems.
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