Improvement in the method of sample stacking for gravity injection in capillary zone electrophoresis.

A method that allows capillary electrophoresis to be used as a microconcentrating technique is presented. An 85-fold improvement in the amount of material that can be injected into a capillary column without loss of resolution is shown. The method can be used for negative- and positive-charged species but it cannot be used for both species simultaneously.