CAPILLARY LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY AND MICELLAR ELECTROKINETIC CHROMATOGRAPHY AS COMPLEMENTARY TECHNIQUES IN ENVIRONMENTAL-ANALYSIS

Applications of capillary electrophoresis (CE) and capillary liquid ch romatography (LC) to environmental analysis have been limited. In this work we present applications of micellar electrokinetic chromatograph y (MEKC) to the analysis of environmental matrices for synthetic dyes. Separations obtained by capillary LC are compared with those obtained under MEKC for seven selected dyes. Both techniques are capable of re solving the subject compounds at high efficiency. Recovery data for sp iked water and soil matrices were obtained for four dyes using solid-p hase extraction cartridges and disks with determination by MEKC-UV det ection. Both pH adjustment via acid and ion-pairing via a cationic sur factant were investigated for isolating dyes. Capillary LC detection w as by continuous-flow liquid secondary ion mass spectrometry (CF-LSI-M S) whereas MEKC used UV detection (214 nm). Application of peak-profil ing at high mass resolution is illustrated with the capillary LC-MS te chnique. Interfacing capillary LC under GF-LSI-MS using the coaxial ar rangement is easier than interfacing CE with this arrangement. MEKC pr ovides a powerful screening and determinative technique, while capilla ry LC-MS provides a confirmatory tool.