Development of a capillary electrophoresis method for the characterization of "palo azul" (Eysenhardtia polystachya)

The tree Eysenhardtia polystachya (Ortega) Sarg. has quite a wide popular use within the traditional Mexican medicine as herbal remedy. Popular practices constitute a relevant enough basis to design optimum analytical methods in order to determine basic principles of diverse medicinal plants. This has become one of the essentials needed to characterize such products, for which it is fundamentally important to develop an efficient and reliable separation method. This work presents the results concerning the development and optimization of a novel CE method for the separation of components from water/etanol (1:1) extracts of E. polystachya, using the following conditions, considered the best obtained: phosphate buffer 10 mM, 20 kV voltage, and pH 8.1 at 214 nm and 50 mM, 12.5 kV voltage with pH 8.1 at 426 nm. The optimization takes into account the parameters associated in the resulting electropherograms, such as number of peaks, migration times, and the Deltat(m) of the neighboring peaks. Under optimal conditions the separation intended was attained within 15 and 20 min for 214 and 426 nm, respectively. The characterization method developed was applied to the analysis of diverse extracts of E. polystachya.