Buffer capacity, ionic strength and heat dissipation in capillary electrophoresis

The composition of background electrolyte (BGE) in capillary electrophoresis (CE) is important for both selectivity and efficiency. Although the importance of pH and ionic strength predominates, attention should also be paid to specific conductivity, heat dissipation and buffering capacity. At a given pH/ionic strength combination, several buffers can in principle be used. Preference should be given to the so called Good type buffers because of the combination of higher buffering capacity and lower specific conductivity. Heat dissipation, leading to disturbances in migration and efficiency can thus be minimised. Buffer performance was calculated using a recently developed buffer selection and evaluation computer program.