Affinity countercurrent chromatography using a ligand in the stationary phase

Area of Science:

• Analytical Chemistry
• Chromatographic Techniques

Background:

• Countercurrent chromatography (CCC) is a liquid-liquid separation technique.
• Improving analyte retention and peak resolution in CCC is crucial for effective separation.
• Ligand addition to the stationary phase is a potential strategy to enhance CCC performance.

Purpose of the Study:

• To investigate the impact of ligand addition to the liquid stationary phase in CCC.
• To demonstrate the versatility of ligand-modified CCC for separating diverse analytes.
• To address challenges such as ligand leakage and enhance sample loading capacity.

Main Methods:

• Countercurrent chromatography (CCC) with a ligand-modified liquid stationary phase.
• Separation of amino acid derivatives using N-dodecanoyl-L-proline-3,5-dimethylanilide.
• Separation of catecholamines and dipeptides using bis-(2-ethylhexyl)phosphoric acid.
• Incorporation of a ligand-free stationary phase as an absorbent to prevent ligand leakage.

Main Results:

• Ligand addition significantly improved analyte retention time and peak resolution.
• Successful separation of various amino acid derivatives, catecholamines, and dipeptides was achieved.
• Elimination of ligand leakage by using a ligand-free absorbent phase.
• Over 10-fold increase in sample loading capacity was observed.
• Enhanced applicability for pH-zone-refining CCC.

Conclusions:

• Ligand-modified CCC offers enhanced separation capabilities comparable to chiral, ion, and affinity chromatography.
• The technique effectively resolves complex mixtures and improves chromatographic performance.
• The method provides a robust solution for ligand retention and increased sample throughput.