Micellar electrokinetic chromatography: methodological and instrumental advances focused on practical aspects
1Department of Analytical Chemistry, Rabanales Campus, University of Cordoba, Cordoba, Spain. qa1sirom@uco.es
Electrophoresis
|December 25, 2008
Summary
This review covers new methods and tools to boost sensitivity and resolution in Micellar Electrokinetic Chromatography (MEKC). Key improvements include on-line sample preconcentration and advanced buffer additives for better separation performance.
Area of Science:
- Analytical Chemistry
- Separation Science
Background:
- Micellar Electrokinetic Chromatography (MEKC) is a powerful separation technique.
- Enhancing sensitivity and resolution remains crucial for broader MEKC applications.
Purpose of the Study:
- To review recent advancements in MEKC methodology and instrumentation.
- To highlight strategies for improving sensitivity and resolution in MEKC analyses.
Main Methods:
- Methodological improvements: On-line sample concentration (stacking, sweeping), in-capillary derivatization, flow-injection coupling.
- Buffer modifications: Organic modifiers, ionic liquids, surfactants, CDs, vesicles, carbon nanostructures.
- Instrumental enhancements: Mass Spectrometry (MS) coupling, Laser-Induced Fluorescence (LIF) detection.
Main Results:
- On-line concentration techniques significantly boost analyte detectability.
- Diverse buffer additives and novel surfactants improve separation selectivity and resolution.
- Advanced detection methods like LIF offer high sensitivity, while MS coupling challenges are being addressed.
Conclusions:
- Significant progress has been made in enhancing MEKC sensitivity and resolution through innovative methods and instrumentation.
- Future directions may involve further integration of hyphenated techniques and novel detection strategies.
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