Related Experiment Videos
On-line sample concentration in micellar electrokinetic chromatography using cationic surfactants
J B Kim1, J P Quirino, K Otsuka
1Faculty of Science, Himeji Institute of Technology, Kamigori, Hyogo, Japan. jbkim@sci.himeji-tech.ac.jp
Journal of Chromatography. A
|May 31, 2001
Summary
Two online concentration techniques, sample stacking and sweeping, significantly boosted detection sensitivity in micellar electrokinetic chromatography using cationic surfactants. Sweeping achieved a 1000-fold increase, enabling ppb detection limits for naphthalenesulfonic acids.
Area of Science:
- Analytical Chemistry
- Separation Science
Background:
- Micellar electrokinetic chromatography (MEKC) is a powerful separation technique.
- Online preconcentration methods are crucial for enhancing detection limits in MEKC.
Purpose of the Study:
- To evaluate sample stacking and sweeping as online concentration techniques in MEKC.
- To assess the effectiveness of cationic surfactants as pseudostationary phases for these techniques.
Main Methods:
- Utilized tetradecyltrimethylammonium bromide and cetyltrimethylammonium chloride as cationic surfactants.
- Employed sample stacking and sweeping for on-line sample concentration.
- Analyzed naphthalenesulfonic acids using UV detection.
Main Results:
- Sample stacking yielded approximately a 10-fold increase in peak height.
- Sample sweeping resulted in approximately a 1000-fold increase in peak height.
- Sweeping achieved concentration limits of detection for naphthalenesulfonic acids between 0.96 and 0.47 ppb without preconcentration.
Conclusions:
- Both sample stacking and sweeping are effective online concentration techniques in MEKC.
- Sample sweeping offers a significant improvement in detection sensitivity.
- Cationic surfactants are suitable pseudostationary phases for enhancing sensitivity in MEKC.