Application Of Capillary Electrophoresis In Drug Analysis And Food Safety

Capillary electrophoresis (CE) is a new technique of separation andquantitation regrouping different modes of separation, which has raised worldwideinterest during recent years and many applications in the separation. The mainadvantages of CE compared with high performance liquid chromatography (HPLC) arethe high efficiency, powerful resolution, fast separation, low instrumental cost, and lowconsumption of samples and reagents.In this paper, we have developed new methodswith capillary electrophoresis to research binding interaction of two drugs paclitaxeland propafenone with human serum albumin; make use of capillary electrophoresiswith laser induced fluorescence to investigate glipizide in human plasma; developenew methods with capillary electrophoresis to screening and determination of Sudandyes in food stuff.The thesis consists of two chapters:Chapter one: The review of application of capillary electrophoresis in druganalysis and food safetyIn this part, a review about capillary electrophoresis, the application of capillaryelectrophoresis in drug analysis, analytical methodology for drug and protein bindingstudies and food safety were summarized in detail according to the articles in recentyears.Chapter two: Research reports which are composed of four components asfollows:1. Study of paclitaxel-human serum albumin interaction by capillary zoneelectrophoresisA simple and rapid capillary zone electrophoresis method (CZE) was developedto study paclitaxel -human serum albumin interaction. The UV wavelength was set at214 nm, the applied voltage was 21KV and all separations were performed in50mmol/L Na₂B₄O₇-Na₂CO₃ (pH=10) buffer. Under these optimal conditions, thebinding constant and the number of binding site at different temperature wereK298K= 1.7×10⁴ Lmol^-1, n_298K=4.1 ; K_310K=3.4×10⁴ Lmol^-1, n_310K=3.0, respectively. Theresults confirm that the CZE method is simple, fast, low running cost and accurate for the measurements of HSA-drug interaction.2. Study of propafenone-human serum albumin interaction by capillary zoneelectrophoresispropafenone-human serum albumin interaction was studied by capillary zoneelectrophoresis method (CZE) with UV detection. The UV wavelength was set at 214nm, the applied voltage was 17KV and all separations were performed in 50mmol/LNa₂B₄O₇-NaHCO₃ (pH=10) buffer. Under these optimal conditions, the bindingconstant and the number of binding site at different temperature were K_Z98K=1.65×10⁶Lmol^-1, n_298K=1.15; K_310K=1.92×10⁶ Lmol^-14, n_310K=1.23, respectively. We also make useof UV and fluorescence spectrum to study the binding mechanism. The results confirmthat the CZE method is simple, fast, low running cost and accurate for themeasurements of binding interaction.3. Rapid, specific capillary electrophoresis with laser-induced fluorescencemethod for determination of glipizide in human plasma.A sensitive capillary electrophoresis with laser-induced fluorescence method(CE-LIF) was developed and validated for fast determination of glipizide in humanplasma. Glipizide has been widely used to treat Type 2 diabetes, which has feazedmany people. CE-LIF is a powerful approach to determine trace amounts of analytes ina complex biological matrix. After optimize separation conditions, glipizide and itsinternal standard carbamazepine were measured, the linearity is from 2.24×10^-11～1.12×10^-8 mmol/L(r=0.9986), the limit of quantification for glipizide in plasma was1×10^-10mmol/L with good accuracy and precision. The results confirm that the methodis simple, fast, low running cost and accurate for the measurements of glipizide inhuman plasma.4. Rapid separation and Determination of Sudan dyes by capillary zoneelectrophoresis.The determination of four Sudan dyes which has been found in food products andcaused panic among customers by means of capillary zone electrophoresis (CZE) withUV detection was proposed. The separation of a mixture of the standards (â… ,â…¡,â…¢andâ…£) was achieved under the conditions that the background electrolyte is 50 mmol/LNa₂B₄O₇—K₂HPO₄ (pH=8.3) and applied voltage is 23KV. Four azo-dyes werebaseline separated with limits of detection ranging from 1 to 5μg/ml. The resultsdemonstrate the applicability of the method to screening and determination of Sudan dyes in food stuff.