Exact electric field strength over the packed capillary electrochromatography column bed, theoretical considerations and practical determination

On the basis of the experiments, it was proved that Ohmʹs law holds true in a capillary electrochromatography (CEC) column. By using the additivity of the potential drop over the packed and unpacked sections, the exact values of the electric field strength over the packed CEC column bed were determined experimentally. The ratio of the resistance of packed CEC column sections to that of an open capillary of the same length ( R ¯ p / R o , L p ) were calculated. Some theoretical calculations were made to show how some structural parameters of particle lattice affect the resulting R ¯ p / R o , L p value of the column bed formed accordingly. It is suggested that to correctly elucidate the EOF phenomenon in a CEC column, the potential drop over the packed and unpacked column sections, Ep and Eo, should be accounted for respectively, rather than using the average field strength over the total column length.