Aldehydes And Acids By Capillary Electrophoresis Separation

High-performance capillary electrophoresis is a kind of new electrophoresis technology with high efficiency and rapid separation, which carries out separation by a ion or charged ions taking high voltage electricity for motive force and in accordance with the difference of mobility and distribution behaviors of all the components of samples. It has some advantages of high efficiency, fast analysis, little sample consumption, high automaticity, simple operation and little reagent dosage.Because of HPCE having so attractive advantages, it has shown extremely important application prospects in the life sciences, biotechnology, medical drugs, environmental science, forensic science and other fields. In last ten years, capillary electrophoresis technology develops rapidly, especially in recent years it has been one of the most-watched and most advanced technologies in biochemistry and analytical chemistry.Some aldehydes are recognized as the source of allergy. Hence the study of aldehydes is paid people's more and more attention. Aromatic carboxylic acid compounds have a very wide range of application in foods, drugs and other productions. In these compounds, sodium benzoate is often used as food preservatives in flavoring compounds, but excessive dosage will have a great toxicity in the human body. As a result, determination of the content of aromatic acids has great significance. Fatty acid is widely distributed in nature, which is an important nutrient metabolism material in organism and plays an important role in regulating certain metabolic and physiological functions. Bile acid is widely found in a variety of animals'bile, which can emulsify hydrophobic molecules in water, improve digestion, balance cholesterol, digest fat, and prevent the formation of gallstones. Therefore the determination of them has an important significance in further study on physiology and pathology, and clinical diagnosis.As these biological molecules have no or weak ultraviolet absorption and the low contents cannot be detected directly by UV detection, chemical derivation has been developed in the separation of aliphatic aldehydes, aromatic carboxylic acid, fatty acids and bile acids. The results are satisfactory.The thesis consists of three chapters.Chapter OneThe developments of capillary electrophoresis (CE) and the its applications in pharmaceutical analysis, biomolecular separation, genetic engineering, clinical medicine and many other fields have been simply introduced. At the same time, the separation strategy of analyte by capillary electrophoresis and the related basic knowledge are reviewed.Chapter Two A simple and mild method for the separation of aldehydes based on a condensation reaction with 9,10-phenanthrenequinone as labeling reagent with nonaqueous capillary electrophoresis has been developed. The results indicate that seven aliphatic aldehyde derivatives and actualspecimen can be achieved baseline resolution under the proposed conditions.Chapter ThreeThe separation of acid based on a condensation reaction with 9,10-phenanthrenequinone as labeling reagent with capillary electrophoresis, The principal contents of this chapter consist of four parts.3.1 The benzoic acid and substituted benzoic acids can be well-separated with 7-amino-1,3-naphthalenedisulfonic acid as labeling reagent by capillary zone electrophoresis. The optimum conditions are as follows:30 mmol/L borate,15 mmol/Lβ-CD, pH 9.5. It has been applied to the determination of the content of benzoic acid in light soy sauce and dark soy sauce with satisfactory results.3.210 short chain fatty acids(C1～C10)can be well-separated with 7-amino-1,3 naphthalene disulfonic acid as labeling reagent with capillary zone electrophoresis. The optimum conditions are as follows:30 mmol/L borate buffer,15 mmol/Lβ-CD, pH 9.5, temperature 20℃, pressure 50 mbar, injection time 8 s, and the funaria hedw and selaginella samples are qualitatively and quantitatively detected under the optimum conditions with satisfactory results finally.3.3 A simple and mild method for the separation of 10 long fatty acids based on a condensation reaction with 7-amino-1,3-naphthalene disulfonic acid as labeling reagent with CZE-UV has been developed. Under the optimum conditions,10 fatty acids can be well-separated within 18 min. and the brachymenium nepalense sample is qualitatively and quantitatively detected under the optimum conditions with satisfactory results finally.3.46 bile acids can be well-separated based on a condensation reaction with 7-amino-1,3-naphthalenedisulfonic acid as labeling reagent with capillary zone electrophoresis. The optimum conditions are as follows:25 mmol/L borate, pH 9.5; column temperature,20℃. The method was rapid, simple and effective.