| Chiral drug and chiral pesticide enantiomers are increasingly attaching great importance to the international community in differences of efficacy, pharmacology, metabolism and toxicology, which has become two problems to be solved urgently in current drug safety and food safety. Therefore, the development of chiral separation materials and chiral analysis technology not only has important research significance, but also has a good application prospects. In this paper, the preparation and characterization of derivatized ?-cyclodextrin-bonded chiral stationary phase for high-performance liquid chromatography(HPLC) and open-tubular capillary column with sulfobutyl-beta-cyclodextrin for electrochromatography(CEC) were respectively carried out. By optimizing various separation conditions, several common chiral drug and pesticide enantiomers, such as naringin, nicardipine, hexaconazole, flutriafol, on the new columns with cyclodextrin ligand were successfully separated. The rapid determination of enantiomeric contents of above compounds were also established by HPLC and CEC, respectively. It could be used as monitoring tools for the drug safety and food safety analysis. The chiral HPLC column packed with the ordered mesoporous silica modified by ?-cyclodextrin derivatives have high enantioselectivity, stable chromatographic performance and excellent permeability, which is conducive to rapid analysis of chiral drugs and chiral pesticides. Meanwhile, the capillary wall modified with charged cyclodextrin can generate strong the electroosmotic flow(EOF). The chiral separation ability of CEC column with charged cyclodextrin was improved through the synergic interaction between the chiral selectors of cyclodextrin on the stationary phase and in the mobile phase. The chiral CEC analytical method is a low cost, environmental friendly micro-separation technology. By focusing on optimizing the separation conditions and the determination for actual samples, it is expected that the proposed method will be more widely used in the field of chiral drug analysis in the future.1. High performance liquid chromatography and capillary electrophoresis as the two main methods of chiral separation have made important progress. In this paper, the development of stationary phase, chiral drug analysis methods and chiral additives electrophoresis method were summarized, as the theoretical basis of this thesis and research work.2. By using a homemade phenylcarbamate derivatived ?-cyclodextrin-bond SBA-15 chiral stationary phase, and methanol water as mobile phase, the naringin enantiomers were successfully resolved. The effect of mobile phase composition, column temperature and detection wavelength on the chiral separation of naringin were investigated. The optimized chromatographic conditions of naringin enantiomers were as follows: methanol-water(55:45, v/v) as the mobile phase, a flow rate of 0.5 mL/ min, column temperature at 20 oC, an injection volume of 10 ?L, the detection wavelength at 285 nm. Based on the above conditions, the quantitative analysis method of naringin enantiomers in Chinese herbal medicine, including pummelo peel, citron, fructus aurantii and shaddock peel were established. The measured content of the two naringin enantiomers were 10.42 mg/g and 15.84 mg /g for pummelo peel; 15.39 mg/g and 49.52 mg/g for citron; 16.53 mg/g and 95.80 mg/g for fructus aurantii; 18.47 mg/g and 30.98 mg/g for shaddock peel, respectively. The linear relationship of naringin enantiomers were observed in the concentration range of 0.5 ~ 500 ?g/m L(r?0.995), the detection limits were 0.04 ?g/mL, the recoveries were greater than 91.31% with RSDs 1.54%(n=5) for both two isomers. Chinese herbal medicine is a treasure of natural medicine containing lots of nature active chiral compounds. Thus, the chiral drug monitoring should pay attention to herbs.3. The enantiomers of chiral pesticides often have different insecticidal activities, human toxicity and environmental behavior, and the residue of chiral pesticides has brought new problems to food safety. A ureado derivatizated ?-cyclodextrin-bond SBA-15 chiral stationary phase(UCDSP) was prepared and successfully used to enantoseparate of chiral pesticide fungcide hexaconazole by HPLC and some effects of mobile phase composition, pH value, column temperature etc. on the chiral separation were studied. The results showed that the optimal conditions including methanol water(60:40, v/v) as mobile phase, a 0.5 m L/min of flow rate, column temperature at 20 oC, detection wavelength at 230 nm. The resolution of the hexaconazole enantiomers was 2.26 within 15 min. A new method for the rapid determination of the enantiomers in apple samples was established under the above optimized chromatographic conditions. A good linear relationship was found in the concentration range of 0.5~125 ?g/mL for the two hexaconazole enantiomers(R?0.9998). Acorrding to 3 times to signal-to-noise, the detection limits of two enantiomers were less than 25 ?g/kg. The recoveries of two enantiomers by standard addition were 88.0%~97.2% with RSD ? 0.98% and 1.2%(n=5). The result showed that the chemical and chromatographic properties of ureado-?-cyclodextrin CSP were stable, and highly selective to the triazole pesticide enantiomers. The preparation method of the UCDSP column was simple at low cost.4. The preparation and characterization of capillary electrochromatographic column modified with sulfobutyl-beta-cyclodextrin were carried out. The capillary wall with negative charge sulfobutyl-beta-cyclodextrin can generate strong electroosmotic flow. By the synergistic effect of the cyclodextrin chiral ligands on the stationary phase and in the mobile phase, cardiovascular drug the nicardipine enantiomers, were successfully separated within 8 min. The effects of the composition of mobile phase, the content of the additive, the operation voltage and the sampling mode on the separation resolution were discussed. At the same time, the determination of enantiomer in nicardipine tablets was established. Measured concentration of nicardipine enantiomers were 19.65 mg/tablet, 19.26 mg/tablet for the first tablets; 19.34 mg/tablet, 19.62 mg/tablet for the second tablets, respectively. The preparation method is simple and convenient. The analytical method has higher reproducibility with little solvent consumption, which has a certain practicality.5. In addition to the analysis of drug, but also the open-tubular CEC column modified with sulfobutyl-ether-?-cyclodextrin was also extended to chiral fungicide flutriafol enantiomers determination in fruits and vegetables. Some effects including additive concentration, pH value, applied voltage, temperature and the content of organic modifier on the chiral separation were investigated. The optimized mobile phase consisting 10 mmol/L sodium borate(pH=9.2), 3.0 mmol/L sulfobutyl ether-?-cyclodextrin and 15% volume fraction of methanol. The practical applied voltage was 15 kv, a temperature of 20 oC, pressure sampling(3 psi×3 s) and the detection wavelength at 204 nm. Under the above conditions, the resolution of flutriafol enantiomers was up to 1.85, the analysis time is only 8 ~ 12 min. The fruit and vegetable samples, such as cucumber, pear, apple and tomato were extracted with acetonitrile, purified with magnetic graphitized carbon. Under the optimal condition, the determination of enantiomers residues in fruits and vegetables were developed. Flutriafol enantiomers in range of 1.3 ~ 250 ?g/mL showed good linear relationship. The recoveries of flutriafols from samples were more than 94.6%, with RSDs ?1.79%. According to the three times signal-to-noise, detection limits of the flutriafol enantiomer were 25 ?g/kg for both enantiomers. The method is simple, rapid, little solvent consumption, low cost and low environmental pollution. |
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