Capillary Electrophoresis Coupled On-Line with Flame Photometric Detection:Determination of Alkylphosphonic Acids

摘要

The separation performance and sensitivity of an earlier developed system whichuses capillary electrophoresis coupled on-line with a flame photometric detector (originally developed for gas chromatography) are considerably improved. The liquid junction used in order to decouple the electrical field shows a negligible influence on the performance of the system as compared with on-line UV detection. The system is used to determine alkylphosphonic acids, which are the hydrolysis products of nerve agents. By using on-column sample concentration techniques the detection limits for the alkylphosphonic acids in water are in the range of 0.1-0.5 micro g/ml. The first results obtained during interlaboratory tests using capillary electrophoresis coupled with flame photometric detection as fast screening method to detect the presence of alkylphosphonic acids in aqueous extracts or water samples are promising.