Heat-Associated Field Distortion in Electro-Migration Techniques

Electro-migration techniques, such as electrophoresis, are widely utilized in analytical sciences. If a single electrolyte is used, the field strength is typically assumed to be well-defined. Heat-associated field distortion (HAFD) has been suggested as a result of the nonuniform heat dissipation throughout the electrolyte; however, it has never been experimentally studied. Here, we experimentally demonstrated HAFD for the first time. We used capillary electrophoresis (CE) with a capillary having parts with different heat dissipation efficiencies. Our experiments showed a difference in field strength of approximately 1.5 times between the different parts of the capillary for a typical CE electrolyte. This result suggests that HAFD is a well pronounced phenomenon that can be a potential source of errors and instabilities in electro-migration experiments.