Comparison of Capillary Zone Electrophoretic Techniques Combined with Indirect UV, Direct UV, and Mass Spectrometric Detection for the Determination of Underivatized Amino Acids and Vitamin B₆ in Infusion Solutions

Abstract

Different methods based on capillary zone electrophoresis (CZE) for the determination of underivatized amino acids and vitamin B₆ in infusion solutions are described and compared. Acidic and basic carrier electrolytes have been investigated with respect to their suitability for the separation of the selected analytes. Focusing on detection, indirect and direct UV detection at different wavelengths, as well as mass spectrometric (MS) detection have been tested, with the main emphasis set on their ability to provide quantitative results for all analytes in a single run. Finally, an acidic carrier electrolyte based on phosphoric acid and direct UV detection at 195 nm, were found to be the best suited solution for the determination of the six amino acids and vitamin B₆ in the investigated real samples.

Keywords:

• Capillary electrophoresis
• Mass spectrometric detection
• Amino acids
• Infusion solutions
• Direct UV
• Indirect UV