INFLUENCE OF CAPILLARY DIMENSIONS ON THE PERFORMANCE OF A COAXIAL CAPILLARY ELECTROPHORESIS ELECTROSPRAY MASS-SPECTROMETRY INTERFACE

The dimensions of the capillaries used to construct a typical coaxial capillary electrophoresis-mass spectrometry (CE-MS) interface, i.e. th e inner diameter, the outer diameter and the wall thickness, have been shown to affect the performance of the CE-MS system. The influence of these parameters has been investigated in both MS and MS-MS modes. Th e initial results indicate that by reducing all the sheath capillaries ' dimensions and the CE capillary outer diameter, better operation and increased sensitivity can be achieved. The capillary arrangement whic h gives optimum sensitivity and stable operation has been suggested.