Cyclodextrins as Chiral Selectors in Capillary Electromigration Techniques

Area of Science:

• Analytical Chemistry
• Separation Science
• Supramolecular Chemistry

Background:

• Cyclodextrins (CDs) are cyclic oligosaccharides with unique toroidal structures.
• Their ability to form inclusion complexes makes them valuable in various scientific fields.
• CDs are widely recognized as effective chiral selectors in capillary electromigration techniques.

Purpose of the Study:

• To provide an overview of cyclodextrin properties and their application in enantioseparation.
• To discuss the principles and strategies for chiral separations using capillary electrophoresis.
• To demonstrate the enantioseparation of charged analytes using native and modified cyclodextrins.

Main Methods:

• Capillary electrophoresis (CE) was employed as the primary separation technique.
• Native beta-cyclodextrin (β-CD) was used for separating a negatively charged analyte.
• Sulfated beta-cyclodextrin (a negatively charged CD derivative) was used for a positively charged analyte.

Main Results:

• Successful enantioseparation of 1,1'-binaphthyl-2,2'-diyl hydrogen phosphate (negatively charged) using native β-CD.
• Effective enantioseparation of ofloxacin (positively charged) using sulfated β-CD.
• Demonstrated control over enantiomer migration order by adjusting background electrolyte pH and sulfated β-CD concentration.

Conclusions:

• Cyclodextrins are highly effective chiral selectors for capillary electrophoresis.
• Method development strategies involving cyclodextrins allow for tailored enantioseparation.
• Experimental conditions significantly influence the separation and migration order of enantiomers.