Capillary electrochromatography - Applicability to the analysis of pesticides and compounds of environmental concern and the theory of electroosmosis

The applicability of capillary electrochromatography to the automated analy sis of pesticides and phthalate esters that are of environmental concern wa s assessed. Reversed phase packing materials were compared. Column to colum n and run to run reproducibility was established. Peak height with an inter nal standard gave the best reproducibility. Faster analysis than alternativ e HPLC methods was demonstrated for a mixture of the insecticide pirimicarb and related pyrimidines. The relationship between the concentration of an analyte in a sample and at the detector was determined by the use of radio- labelled C-14- pirimicarb. The volume fraction of the liquid zone was 0.64. The possibility of electroosmosis through the pores is discussed with refe rence to the Rice-Whitehead model for electroosmotic flow in a capillary. A new parameter, the effective pore size is used in equations for electroosm osis through porous packings.