Graphene oxide coated capillary for chiral separation by CE

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Chiral separation is crucial in pharmaceuticals and chemical analysis.
• Developing efficient and selective separation techniques remains a challenge.
• Graphene oxide (GO) offers unique properties for surface modification and separation applications.

Purpose of the Study:

• To develop a novel graphene oxide (GO) coated capillary for chiral separation in capillary electrophoresis (CE).
• To evaluate the performance of the GO-coated capillary for separating specific chiral isomers.
• To assess the precision, reproducibility, and sensitivity of the developed method.

Main Methods:

• Fused silica capillaries were coated with graphene oxide (GO).
• Coating was characterized using Scanning Electron Microscopy (SEM), energy-dispersive X-ray spectroscopy, and Raman spectroscopy.
• Chiral separations of ephedrine-pseudoephedrine (E-PE) and β-methylphenethylamine (β-Me-PEA) isomers were performed using CE with the GO-coated capillary under optimal buffer conditions.
• Method precision, reproducibility, and limits of detection (LOD) were evaluated.

Main Results:

• Successful coating of fused silica capillaries with graphene oxide was confirmed by characterization techniques.
• The GO-coated capillary effectively separated E-PE and β-Me-PEA isomers without requiring a chiral selector.
• Excellent precision was observed with relative standard deviations (RSDs) for migration times ranging from 1.35-1.41% for E-PE and 0.97-3.50% for β-Me-PEA.
• The method achieved limits of detection (LOD) of 3 μM for E-PE isomers and 18 μM for β-Me-PEA isomers.

Conclusions:

• Graphene oxide coated capillaries provide a promising platform for efficient chiral separations in CE.
• The developed method offers good precision, reproducibility, and sensitivity for separating critical chiral isomers.
• This approach eliminates the need for external chiral selectors, simplifying the separation process.