ANALYSIS OF CATIONS AND ANIONS IN SMALL VOLUMES USING MICRO-LC AND CE

Inorganic ions can be analyzed in small volumes using micro-liquid chromatography (micro-LC) and capillary zone electrophoresis (CE). Results for the analysis of alkali, alkaline earth, and ammonium cations as well as the main organic and inorganic anions are given and discussed. For the determination of the cations in micro-LC and CE, cerium(III) was chosen as eluent and electrolyte, respectively. Micro-LC anion analysis was carried out with hexacyanoferrate(II) and -(III) and indirect photometric detection. In CE 2,5-dihydroxybenzoic acid was used as the fluorescent electrolyte for indirect detection. For CE sample introduction an injection port was developed to handle volumes smaller than 1 muL.