| Capillary electrophoresis (CE) emerged in the 1980s as a highly efficient technique for analysis of complex mixtures in extremely small samples with outstanding resolving power. Because of its relatively short separation time, simple instrumentation and low operational cost, CE has been applied more and more widely. Because of the small sample volumes, the narrow capillary column internal diameter and the extremely small amount of components, the detectors without high sensitivity have become a main obstacle to broaden the application of CE. Currently, UV-Vis absorbance detectors are applied in most commercially available CE instruments owing to their wider application and lower operational cost. However, because the internal diameter of capillary is usually less than 100 u m, the optical path length is limited, which in turn limit its sensitivity seriously. The sensitivity of electrochemical detectors for CE is less dependent on the sample volume and high sensitivity could be achieved, but the contamination of electrode surfaces could be a troublesome problem in practical sample analysis. Mass-spectroscopy detector is very sensitive and accurate, however, it is too expensive, which in turn limits its application.Laser-induced fluorescence (LIF) detector is one of the most sensitive methods applied in CE because of its low background and extremely small sample volume. Samples are determined after excited by laser. To nonfluorescent analytes, additional efforts are required for introducing fluorophores through pre and post column derivation. The application of LIF with CE becomes more and more widely. The application fields include environmental and clinical analysis, peptide and protein analysis, single cell and DNA analysis. With the development of laser technology, multi-dimension laser equipments including wavelength discerned, time discerned and polarized fluorescence detectors are newly emerged, which will broaden much to application of CE-LIF.The thesis consists of four parts:Part one: A method using carboxymethyl-p-cyclodextrin (CM-(3-CD) as selector for chiral separation of amino acids by capillary electrophoresis and laser-induced fluorescence detection was studied. Resolution was better than that obtained by 0-CD orHP-beta-CD. Fluorescene-5- isothiocyanate (FITC) was used to derive amino acids. Seven kinds of FITC-amino acids (Leu, Pser, Ala, Val, Met, Ser and Trp) were chiral separated entirely under the optimum conditions. Within-day precision is between 2.0-4.6% and between-day precision is between 2.5-4.8%. The detection limits were between 0.1-2.0 xlO-8mol/L. The method offered high sensitivity and separation efficiency and the result was satisfactory.Part two: Propranolol could react with FITC in an appropriate condition, and then derivative FITC-PPL was achieved. FITC-PPL was chiral separated used p-cyclodextrin as chiral separator and 75 mmol/L borate solution as buffer. Both within-day precision and between-day precision were less than 5%. Both detection limits of R-PPL and S-PPL were 1.24ng/mL. The linear range of R-PPL was 3.0-1 X 103 ng/mL and that of S-PPL was 2.0-1 X 103 ng/mL. The method offered a high sensitivity and can be used to research pharmacokinetics of propranolol.Part three: A new method was established to detect atenolol in plasma. The assay had a wide range (5-5000 ng/mL) of linearity and a detection limit of 1.5 ng/mL with acceptable intra- and inter- assay reproducibility using small volume of plasma (75 ul). After oral administration of a suitable dose of atenolol to rabbits, blood samples were collected twelve times during 24 h. After centrifugalization, these plasmas were ultrafiltered in ultrafiltration tubes at 8000 rpm for 40 min. Then the serums were derived with 5 x 10-4 mol/L fluoresceine-5-isothiocyanate (FITC). The derivatives were determined by capillary electrophoresis and laser-induced detection. Other components including a variety of amino acids in plasma did not interfere the determination of atenolol, because the migration times of FITC-amino acid...
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