| During the last two decades, capillary electrophoresis (CE), based on the separation of charged molecules through a small capillary under the influence of an electric field, has emerged as a powerful analytical separation technique for the determination of numerous analytes from organic molecules to macromolecules such as DNA and proteins with attractive features, such as high resolving power and small sample volume. Nowadays, it is utilized for the daily assays as an excellent complement to high-performance liquid chromatography.Electrogenerated chemiluminescence (ECL) detection is based on the chemiluminescence emission related directly or indirectly with oxidation or reduction at an electrode surface. It is treated as an ideal detection technique which can be interfaced with capillary electrophoresis because of its high sensitivity, simple operation and the low cost of apparatus used. Ru(bpy)32+ is considered as the most efficient, thoroughly examined, and widely used ECL reagent. It can be oxidized to Ru(bpy)33+ on the working electrode under certain potential. Subsequently, Ru(bpy)33+ reacts with the tertiary amine group and then changes to the excited state Ru(bpy)32+*, which can release light by returning to the ground state.The main work of this thesis is summarized as follows:1. A sensitive method combining the capillary electrophoresis and the end-column Ru(bpy)32+ ECL detection to determine thioridazine hydrochloride is presented. Factors that influence on the ECL intensity and the column efficiency were optimized, such as injection time, injection voltage, and the buffer pH value and so on. When the concentration of thioridazine hydrochloride increased from 2μM to 800μM, the ECL intensity increased linearly. This method can be utilized for the detection of thioridazine hydrochloride in urine and its routine quality control analysis.2. Capillary electrophoresis electrochemiluminescence(CE-ECL) separation system was employed to detect difenidol hydrochloride. A linear ECL response for difenidol hydrochloride over the range from 1.0×10-6 to 6.0×10-5 M was established with a detection limit of 1.0×10-7 M. This method was successfully utilized to investigate the interaction of hemoglobin with difenidol hydrochloride.The number of binding sites and the binding constant were calculated as 11.2 and 2.5×103 M-1, respectively.3. The Ru(bpy)32+/CNT/nafion-modified electrode was prepared and applied to the amperometric detection of difenidol hydrochloride. This method is simple and reproducible. The sensor was employed for the determination of the active ingredients in the tablets containing difenidol hydrochloride. It's evident that such kind of sensor can also be used for the detection of other tertiary amine-containing analytes.
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