Novel Separation Media with Metal Oxide Nanostructures for Capillary Electrochromatography

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Zinc oxide nanowires (ZnO NWs) show promise as separation media due to biocompatibility and low cost.
• Previous research established ZnO NWs for molecular recognition and liquid phase separation.
• Limited studies explored ZnO NW molecular recognition despite numerous reports on ZnO NWs.

Purpose of the Study:

• To improve the solvent resistance of ZnO NWs.
• To develop a stable and effective separation medium for acidic compounds.
• To evaluate the application of TiO2-coated ZnO NWs in capillary electrochromatography.

Main Methods:

• Coating ZnO NWs with titanium oxide (TiO2) thin layers via atomic layer deposition.
• Developing a TiO2 NW column for separation analysis.
• Conducting capillary electrochromatography with aqueous acetonitrile and weak acids as the mobile phase.

Main Results:

• The TiO2 NW column exhibited high affinity for acidic compounds, particularly phosphate groups.
• The resistance of ZnO NWs to weak acidic buffer solutions was significantly improved.
• Successful control over the elution order of phosphorylated compounds was achieved.

Conclusions:

• TiO2 coating enhances the stability and separation capabilities of ZnO NWs.
• The TiO2 NW column demonstrates potential for advanced separation analysis of acidic biomolecules.
• Multipoint electrostatic interactions between phosphate groups and the NW surface contribute to improved performance.