Partial-filling micellar electrokinetic chromatography and non-aqueous capillary electrophoresis for the analysis of selected agrochemicals.
Selected agrochemicals (s-triazines and phenoxy acids) have been investigated with partial-filling micellar electrokinetic chromatography (PFMEKC) and non-aqueous capillary electrophoresis (NACE). Because these two techniques are compatible for coupling of capillary electrophoresis with mass spectrometry, different conditions affecting the separation efficiency (reproducibility, method linearity) were systematically tested, and the results were compared with those from classical MEKC. The conditions tested included buffer molarity, pH, the concentrations of the organic modifier and surfactant, the applied voltage, the injection time of the sample, and the length of the partial-filling plug. The respective limits of detection (LOD) using UV-detection were determined. Reduction of the electrophoretic raw data using the mobility scale transformation (micro-scale) improved qualitative comparison of the electropherograms and the reproducibility of quantitative data (integrated peak area) thus extending this data treatment from CZE to other endoosmotic flow-driven CE-techniques such as PFMEKC and NACE.
Menzinger
F
F
GSF--National Research Centre for Environment and Health, Institute for Ecological Chemistry, Neuherberg, Germany.
Schmitt-Kopplin
P
P
Frommberger
M
M
Freitag
D
D
Kettrup
A
A