A new dual-electrode and dual-channel electrochemical detection system for capillary electrophoresis

A new dual-electrode and dual-channel electrochemical detection technology for capillary electrophoresis is described, in which two detectors the amperometric detector and the conductometric detector or two conductometric detectors are connected to the same capillary electrophoresis system. The system possesses the advantages of two electrochemical detectors including sparing time, improving the analytical speed and expanding the sample range. The fabrication of the detection cell and the working electrode are convenient. It is easy to assemble and disassemble the working electrode and the separation capillary. With the stainless steel syringe needles and capillary as the guide tubes, the alignment of the working electrodes to the outlet of the separation capillary can be easily done without the aid of three-dimensional adjustor. Different kinds of working electrode and detector can be chosen according to the different analytical aims. By using a laboratory-built filter circuit the signals disturbance generated from different detectors can eliminate effectively. With this system the electroactive (oxidative or reductive) and inert components in a complicated sample can be detected simultaneously. It can also be used to verify analytes. The system is applied to detect real sample with satisfactory results.