Quantitative and selective analysis of lactose by capillary electrophoresis

A GE method has been validated for the analysis of batches of lactose used as a pharmaceutical raw material. This method was shown to be selective for lactose and was found to be quantitative. The separation was achieved due to on-capillary chelation of the lactose with berate ion. The resulting com plex was detected at 195nm. An internal standard is employed to improve inj ection precision and detector linearity. A system peak occurred in the sepa ration and was systematically investigated to show that it was not sample r elated. The method was validated and successfully submitted to regulatory a uthorities and is now in routine use in a number of our quality control lab oratories.