| Capillary electrophoresis (CE) emerged in the early 80s as a highly efficient means of separation for the analysis of complex mixtures in extremely small samples with outstanding resolving power. The relatively short separation times, simple instrumentation and low operational costs make it an intensive exploition. In the application of CE, the detectors without high sensitivity have become a main factor that limits application of CE, because of the small sample volume, the narrow capillary column internal diameter and the extremely small amount of components in samples. Currently, UV-absorbance detectors are employed in most commercially available CE instruments owing to their broad applicability and relatively low cost. However, the optical path lengths are limited by the capillary column internal diameter to usually less than 100m, which in turn seriously limits the sensitivity. Laser-induced fluorescence (LIF) detectors for CE have enjoyed increasing popularity owing to its high sensitivity and low detection limit. However, apart from the considerable extra investment of costly equipment, additional efforts are also required for introducing fluorophores to nonfluorescent analytes through pre or postcolumn derivation. The sensitivity of electrochemical detectors for CE is less dependent on the sample volume, and highly sensitive detection could be achieved, but the contamination of electrode surfaces might also pose problems in the analysis of real samples.Chemiluminescence analysis is a trace analysis method which determines the content of substance according to the light emission of the chemical reaction. In 1877, Radziszeuski found that lophine emitted green light when it reacted with oxygen in the presence of a base This is the first example of Chemiluminescence using a synthetic organic compound. Since then, a number of chemiluminescent compounds have synthesized and studied for their chemiluminescent properties. Chemiluminescence analysis has high sensitivity (Detection limit can be 10-12-10-1mol) , wide linear range (three to six magnitude order), low background and simpler, lower instruments which is suited to post-column detection for very low-volume sample in CE. At present, it becomes less developed detection system for CE. It needs great development in its potential. Without doubt, Chemiluminescence in CE will be widely applied in environment science, biological science and clinical science.The thesis consists of four parts:Part one: A novel chemiluminescence (CL) detection scheme has been developed for detecting seven amino acids (Arg Pro Hyp Met Ser Thr CysH) following capillary electrophoresis (CE) separation. This detection was based on the inhibitory effect of amino acids on the CL reaction between Luminol and BrO" in alkaline aqueous solution. The relative standard deviation (RSD) for the analysis of amino acids was less than 1.5% for the migration time and 4% for the peak height. The limits of detection were from 1+10-6 to 5+10-6mol/L for the 7 amino acids. The method is simple and rapid with satisfactory results.Part two: Based on the inhibitory effect of water-soluble vitamins on the CL reaction between Luminol and BrO" in basic aqueous solution, water-soluble vitamins (VB1,VB6,VK1,Vc,VB2,VB12) can be detected following capillary electrophoresis (CE) separation. The relative standard deviation (RSD) for the analysis of water-soluble vitamins was less than 1% for the migration time and 5% for the peak height. The limits of detection were from 0.8+10-6 to 1.6+10-6mol/L for the 6 water-soluble vitamins. The method can be applied to the determination of amino acids in tablet with satisfactory results.Part three: A novel in-capillary reduction and capillary electrophoresis (CE)-chemiluminescence (CL) method was developed for the analysis of speciation of chromium ions. The proposed method was based on the in-capillary reduction of Cr(VI) with acidic NaHSO3 to form Cr(III) using the chemiluminescence detection of Cr(III). The sample, buffer and NaHSO3 solution segments were in...
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