CAPILLARY ELECTROPHORESIS OF PLANT STARCHES AS THE IODINE COMPLEXES

Much research is currently focused on the use of plant starch as an industrial raw material which can reduce dependence on non-renewable resources. Development of new starch-based products requires effective methods for analysis and characterization of starch and related biopolymers. Most separations methods are not suitable for this application due to the high molecular mass (>10(6)) of starch. We describe here the use of iodine complexation to impart charge and permit detection of starch components in capillary electrophoresis. Amylopectin and amylose are resolved in less than 10 min using iodine-containing buffers in unmodified capillaries. Partial resolution of an oligosaccharide mixture was also demonstrated, indicating potential utility of the method for analysis of smaller biopolymers. The primary basis for separation is shown to be iodine binding affinity, which can be manipulated through control of temperature and iodine concentration.