In-house packing and testing of capillaries for capillary electrochromatography using simple equipment

The feasibility of producing packed capillaries for capillary electrochroma tography (CEC) is evaluated. Emphasis is put on the fact that only material was used that is already available in any LC/CE orientated laboratory. An experimental set-up is developed for filling the capillaries by use of an o rdinary LC pump, and frits are sintered with a glowing resistance wire, fed by a d.c. power supply. Electrochromatography was carried out in an in-hou se built capillary electrophoresis apparatus, without pressurizing the vial s. Under these conditions, the capillaries performed well, producing up to 190 000 plates per meter. Bubble formation did not appear, on condition tha t the mobile phase was thoroughly helium degassed. Even at ambient temperat ure, electrophoresis obeyed Ohm's law up to a voltage of 30 kV, proving tha t Joule heating was not a major concern. (C) 1999 Elsevier Science B.V. All rights reserved.