Methacrylate monolithic columns functionalized with epinephrine for capillary electrochromatography applications.

Area of Science:

• Analytical Chemistry
• Materials Science
• Chromatography

Background:

• Polymeric monoliths are widely used as stationary phases in capillary electrochromatography (CEC).
• Chemical modification of monolith surfaces can alter chromatographic properties.
• Epinephrine, a biomolecule, has potential for surface functionalization.

Purpose of the Study:

• To develop epinephrine-bonded polymeric monoliths for CEC.
• To optimize the synthesis and characterize the modified monoliths.
• To evaluate the chromatographic performance of the new stationary phases.

Main Methods:

• Nucleophilic substitution reaction to bond epinephrine to poly(glycidyl-methacrylate-co-ethylenedimethacrylate) (poly(GMA-co-EDMA)) monoliths.
• In situ Raman spectroscopy for chemical modification confirmation.
• Ce(IV) oxidation and spectrophotometry to quantify bonded epinephrine.
• CEC experiments with alkyl benzenes, aniline derivatives, and substituted phenols.

Main Results:

• Successful synthesis of epinephrine-bonded poly(GMA-co-EDMA) monoliths.
• Approximately 9% of epoxide groups were functionalized with epinephrine.
• Epinephrine-bonded monoliths showed significantly higher retention and altered selectivity compared to parent monoliths.
• Reproducibility of the modified monolithic stationary phases was demonstrated with relative standard deviation (RSD) values below 9%.

Conclusions:

• Epinephrine-bonded polymeric monoliths are effective stationary phases for CEC.
• The modification enhances retention and selectivity, offering improved separation capabilities.
• The developed materials demonstrate good reproducibility for analytical applications.