| The enthusiastic adoption of high performance liquid chromatographic (HPLC) and capillary electrophoresis (CE) has been a great impact on chemical analysis, not only in chemistry and biochemistry but also in toxicology, clinical sciences, environmental science and many other fields.With the special separation characterization, HPLC is one of the fastest developed and the most widely used fields in analytical chemistry. After HPLC method, capillary electrophoresis (CE) is a rapidly growing separation technique with many advantages including high performance, high speed and small sample consumption. It has proved to be powerful tool for the separation of compounds such as amino acids, chiral drugs, vitamins, pesticides, inorganic ions, organic acids, dyes, peptides and proteins, and even whole cells and virus particles.The responsible mechanisms for the separation of components in CE are different from those in liquid chromatography. In view of this, two methods can each other offer orthogonal, complementary analyses. In addition, CE may offer simpler method development, minimal sample volume requirements with almost no organic waste.With the development of modern analytical technology, the method of traditionally conventional analysis has been converted to the trace analysis and even the extreme trace analysis. In order to improve the sensitivity of detection, people have been devoting to amplify signals and renovate the detectors. All the scientific researchers have been expected to obtain the reliable and sensitive results, and this is also a question which claims precedence over all others. However, there is a limit in improving the sensitivity of instrument. So it is an accessible approach to design and synthesize novel high sensitive fluorescent probe to improve detection sensitivity that it is difficulty to achieve the goal withthe conventional analysis. With the development of these novel sensitive probes, the classical analytical method has been developed and made the trace and extreme trace analysis true. Therefore, labeling of the analytes with fluorescent probe has been widely adopted to alter the chemical physical properties of target compounds to make them be analyzed easier with HPLC or CE.In this thesis, the method for the sensitive determination of amino acids and peptides using the synthesized tagging reagents with different chromophores by HPLC and CE with fluorescence or DAD detector has been developed. The thesis consists of four chapters.Chapter one:The development of the labeling reagents and the method of derivatization have been simply introduced. At the same time, the basic knowledge and the further improvement of HPLC and CE are briefly introduced. Then the applications of fluorescence reagents to analyze amino acids and peptides by HPLC or CE are reviewed.Chapter two:9-(2-Carbazole)ethyl chloroformate (CEOC) andl,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC) are synthesized and their structures are characterized.Chapter three:The applications of 9-(2-carbazole)ethyl chloroformate (CEOC) for the analysis of different components by HPLC and CE are investigated. The principal contents of this chapter consist of four parts.3.1 The separation and determination of amino acids and oligopeptides using CEOC as labeling reagent by HPLC with fluorescence detection are studied. The derivatization conditions in conjunction with the gradient elution program are optimized. At the same time, the detection limit and linearity for derivatizedamino acids and oligopeptides are obtained under the optimum conditions. The results indicate that the detection limits for tagged amino acids and oligopeptidesis are at fmol levels (S/N=3) with relatively wide linear range. The established method for the determination of amino acids from extracted four bryphytes is evaluated with satisfactory results.3.2 The separation of derivatized amino acids using CEOC as derivatization agent by capillary zone electrophoresis (CZE) with DAD detectio... |
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