| Chirality is a universal phenomenon in the nature. Enantiomers play an important role in Pharmaceuticals, biochemistry and agrochemical, etc. In many cases, only one isomer in a chiral compound is responsible for the desire activity, while the other isomer may exhibit no therapeutic value and may potentially cause unsuspected adverse effects. In the early 1980s, the routine and rapid analytical resolution of stereoisomerisms was relatively difficult. However, by the early 1990s, significant advancement in the field of separation technology was made so that rapid enantioseparations of optical isomers were becoming routine and commonplace. As understanding of the biological actions of compounds with respect to stereochemistry has been growing, the necessity to investigate the pharmacological and toxicological properties of individual compound has become more apparent. Nowadays the separation and analysis of chiral compounds, especially for the chiral drugs, have important significance, and have already become one of important and extensive research project. So, the urgent demand for analytical methods with highly resolution power and high efficiency is recently increasing for, example, chiral drug purity control, pharmacokinetic, pharmacodynamic studies and clinical research, etc.Capillary electrophoresis (CE) is a recent powerful analytical technique widely applied in resolution research of chiral drugs. CE has some general merits in this area. At first, it is the extremely high peak efficiency. From the viewpoint of a separation this means that in a given chiral selector/selectant pair one can detect in CE the enantioseparation that is impossible to detect using any other instrumental technique. In addition, the different separation modes and the many chiral selectors available make CE techniques a very important tool for chiral analysis in the pharmaceutical field, and a combination of chiral electors is much easier in CE compared to chromatographic techniques. Another important advantage of CE considering the presently tight laboratory budgets and strict environmental limitations is its miniaturized size and consequently, lower costs of use and less environmental pollutions.The dissertation consists of five parts.The chapter 1: Reviewed the developments in the field of enantioseparation of chiral compounds using capillary electromigration techniques, especially on the rcent researchs of chiral separation using clyclodextrins and their derivatives and macrocyclic antibiotics aschiral selectors. In this chapter, the recent development of synergistic effect in capillary electrophoresis enantioseparation is also reviewed.The chapter 2: A chiral separation of Pilocarpine is performed by capillary zone electrophoresis (CZE) on a fused silica capillary with 3 -cyclodextrin (3 -CD) or its derivatives as chiral selectors. The effects of the type and concentration of cyclodextrins used on resolution are studied. We also investigated the effects of other parameters on resolution, such as pH, applied voltage and temperature, and optimized the separation conditions. It was observed that a separation of pilocarpine (Rs=2.79) can be achieved by using 50 mmol/L phosphate buffer at pH 2.5 containing 20 mmol/L hydroxypropyl- B-cyclodextrin (HP- B-CD).The chapter 3: The fradiomycin, streptomycin and kanamycin, belonging to the class of aminoglycosidic antibiotics, has been used as chiral selectors for the separation of two acidic enantiomers BPME1 and BPME2 by capillary zone electrophoresis (CZE) and obtained higher resolution. The effect of aminoglycosidic type and concentration, pH of the background electrolyte, buffer composition, organic modifier type and content, voltage and temperature on enantiomeric resolution were investigated and separation conditions were optimized. It was observed that a good separation of BPME1 and BPME2 can be achieved by using 30 mmol/L fradiomycin in 20 mmol/L borate buffer (pH=7.5) with 10% () methanol.The chapter 4: The addition of an achiral crown ether (18-rown-6) to a...
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