Cereal Chem. 71:397-402   |  VIEW ARTICLE


Wheat Varietal Identification by Capillary Electrophoresis of Gliadins and High Molecular Weight Glutenin Subunits.

W. E. Werner, J. E. Wiktorowicz, and D. D. Kasarda. Copyright 1994 by the American Association of Cereal Chemists, Inc. 

The two main polyacrylamide gel electrophoresis methods used for wheat varietal fingerprinting have been low pH analysis (acid-PAGE) of the alcohol-soluble proteins, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of total gluten proteins denatured and extracted by the detergent SDS in the presence of reducing agents. Equivalent separations have now been achieved in the capillary electrophoresis format. The acid-PAGE separation was accomplished by free solution capillary electrophoresis with a charge-reversed capillary. A separation analogous to SDS-PAGE for the analysis of reduced and denatured gluten was accomplished in the capillary format by including a soluble polyacrylamide sieving matrix in the buffer. This replaceable sieving matrix permitted analysis of multiple samples without cross-contamination between samples. The further addition of a small amount of organic solvent to the sieving matrix allowed for excellent resolution of the high molecular weight glutenin subunits that correlate with breadmaking quality. These techniques also possessed the inherent advantages of capillary electrophoresis: low mass requirements, fast separations, and quantitative analysis through on- capillary UV-detection.