DETERMINATION OF INORGANIC CATIONS AND ANIONS IN SINGLE PLANT-CELLS BY CAPILLARY-ZONE-ELECTROPHORESIS

Investigation of the solute transport in plants on a molecular level r equires the knowledge of the solute distribution between different cel ls within a tissue. Capillary electrophoresis is demonstrated as a use ful technique for the determination of a number of solutes in single p lant cell vacuoles. The procedures of sampling vacuolar sap, dilution of the sample, internal standardization and subsequent injection into the separation capillary are described. Extracted vacuolar sap volumes have been in the range of 20 to 60 pl. For obtained sap volumes >20 p l division of the sample droplet into subsamples is possible. This all ows repeated injections into the CE and thus high reliability of the o btained data and, using different CE systems, the possibility of deter mination of many different species in one vacuolar sample. This is dem onstrated with the determination of inorganic cation and anion concent rations in the same vacuole of individual wheat epidermal cells using indirect UV detection. The applicability of CE for vacuolar analysis i s illustrated with the identification of intercellular solute patterns between different wheat epidermal cell types. (C) 1998 Elsevier Scien ce B.V. All rights reserved.