Comparison of aqueous and non-aqueous capillary electrophoresis for quantitative determination of morphine in pharmaceuticals.

Two capillary electrophoresis methods involving aqueous and non-aqueous electrophoresis media, respectively, have been compared for the quantitative determination of morphine in pharmaceutical preparations. In the aqueous system the separation from other opium alkaloids was achieved using 2,6-di-O-methyl-beta-cyclodextrin as an additive to the electrophoresis buffer. In the non-aqueous system no other additives than the electrolytes were necessary in order to achieve separation of the opium alkaloids. The two methods have been partially validated and compared with a currently used high-performance liquid chromatography method. From the overall point of view the validations show that the three methods are equivalent in performance and that they are appropriate for the purposes they are intended for.