Electrophoresis in nanometer inner diameter capillaries with electrochemical detection

Separations have been achieved in 770- and 430-nm-inner diameter capillarie s. The extremely low sample volumes involved in the study of biological mic roenvironments; such as single cells has led to the desire to develop separ ation techniques in these ultrasmall capillaries. Total sample volumes as l ow as 12 fL have been injected using these nanometer inner diameter capilla ries. Separations of several catecholamines have been accomplished in these submicrometer capillaries using both capillary zone electrophoresis and mi cellar electrokinetic chromatography with end-column amperometric detection .