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Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
A quest for the optimal additive in chiral preparative chromatography
Patrik Forssén1, Robert Arnell, Torgny Fornstedt
1Department of Physical and Analytical Chemistry, Uppsala University, BMC Box 599, SE-751 24 Uppsala, Sweden.
Journal of Chromatography. A
|May 2, 2009
Summary
The choice of acid/base additives significantly impacts chiral chromatography band shapes. Selecting the right additive optimizes enantiomer separation, with specific choices favoring either the first or second eluting enantiomer.
Area of Science:
- Chemical Engineering
- Analytical Chemistry
- Separation Science
Background:
- Acid/base additives in chiral preparative chromatography were historically overlooked.
- Strongly adsorbing additives can unexpectedly alter enantiomer band shapes in modern systems.
Purpose of the Study:
- To investigate the impact of different acid/base additives on enantiomer band shapes.
- To determine the most favorable band shape composition for preparative batch chromatography of racemic mixtures.
Main Methods:
- Demonstration of four binary band-shape compositions: anti-Langmuir/anti-Langmuir, anti-Langmuir/Langmuir, Langmuir/Langmuir, and Langmuir/anti-Langmuir.
- Advanced numerical investigation to evaluate band shape compositions for preparative chromatography.
Main Results:
- The Langmuir/Langmuir composition is optimal for purifying the first eluting enantiomer or both enantiomers.
- The anti-Langmuir/Langmuir composition is optimal for purifying only the second eluting enantiomer.
Conclusions:
- The optimal additive choice depends on the target enantiomer for purification.
- Thorough additive screening is crucial for achieving the best process performance in chiral separations.
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