Study On Biological Samples Analysis By Capillary Electrophoresis Coupled With Chemiluminescence Detection

With the development of biology science, the separation and detection of biological samples has been attached more and more importance. There is an increasing demand to establish a simple, rapid and high resolution technique of the separation and detection in the domain of biology science and its related fields. Capillary electrophoresis (CE) is a powerful technique for the separation due to its virtues of high resolution, efficiency, rapid separation, small analyte consumption and simple instrument. The chemiluminescence(CL) is one of the most sensitive detection methods in CE. CL optical systems are simple, requiring no light sources, and thus providing low background and high sensitivity. When coupled with CE, it can meet the demand of sensitivity and selectivity for the analysis of biological samples simultaneously. Most of the studyies on this field focus on the design of instruments and development of new systems. The application is confined to the detection of inorganic ions, organic molecules and medical molecules, while few studies are concerned with biological samples. In this work, the studies on biological samples ananlysis by CE coupled with CL detection have been exhibited. Firstly, a simple, sensitive CE-CL instrument was set up. A series of novel methods were developed to detect amino acids, folic acid and agmatine in biological samples, such as human serum, monkey serum, monkey stomach, rat brain, rat stomach, human urine, juice and so on. The main contents in the thesis consist of following five parts: 1. Based on the works from others, a novel CL detector for capillary electrophoresis was built in our laboratory. This instrument has the virtues of simple and low-cost operation, stable interface, and high sensitivity. 2. For the first time, CE-CL has been applied to the determination of Glu and Asp in the rat brain and monkey serum. The detection limits were 1.0×10-7 M for glutamic acid (Glu) and 1.3×10-7 M (S/N = 3) for aspartic acid (Asp). The levels of Glu and Asp in monkey serum were quantified for the first time and found to be 1.17±0.17×10-5and1.64±0.19×10-6 mol.L-1 respectively. 3. Using the CE-CL method, 14 amino acids in human serum were detected. Under the optimum condition, baseline resolution was achieved. The results are in accordance with published articles, the recovery is between 91%~108%, and thus providing a reliable and sensitive method for the detection of amino acids in biological samples. 4. Based on enhance effect of folic acids on the CL reaction between luminol and BrO-in alkaline aqueous solution, an on-line CE with CL detector was described for the determination of folic acids in a folic acid tablets and apple juice. And the detection did not be influenced in the enviornment of human urine. 5. For the first time, the agmatine was determined by CE. This method has been used for the determination of agmatine in biological samples, including monkey stomach, rat brain and rat stomach tissues. It is showed that the present method is simple and rapid (the signal can be detected within 100s), The experiment results are consistent with data in literature values.