Determination of catecholamines in single sympathetic nerve cell of rat by capillary electrophoresis with amperometric detection

This paper reports the use of a home-made capillary electrophoresis(CE) with amperometric detection system to the analysis of neurotransmitters in a single sympathetic nerve cell (diameter 15∼25 μm, volume 2∼5 pL) of rat. After enzymolysis the cells were isolated. Sampling of the fresh whole cell was performed through electromigration by directly drawing a cell into the tip of a capillary and lysing the cell inside the capilary as observed under the microscope. The catecholamines in a single cell were separated by CE at the separation potential of 15 kV. Electrochemical detection was performed at 0. 7 V vs. SCE. Isoproterenol was selected to be the internal standard for the determination of norepinephrine (NE) and epinephrine(E) in a single sympathetic nerve cell. The detection limits for NE and E are 57 amol and 59 amol, respectively. The average analytical results of NE and E in eight single sympathetic nerve cells of rats are 445 amol and 65 amol/per cell, respectively.