| Chiral is one of the natural properties of life evolution and development,and many of the living matter,such as protein,are chiral.The enantiomers of chiral drugs and pesticides display different efficacy,toxicology and metabolic pathways when taken into the human body,which is closely related to people's health,is increasingly attracted the attention of the international community.How to efficiently separate and accurately determine the content of the enantiomers will become a new issue of drug safety and food analysis.The continuous development of new separation materials and chromatographic techniques is the key to solve these chiral problems.The?-cyclodextrin chiral stationary phases have excellent chiral resolution,chromatographic reproducibility and extensive inclusion guests,and their preparation method is simple process,low cost and strong practicability.In particular,based on the functionalization of ?-cyclodextrin port,the introduction of a variety of sites,combined with the formation of the cavity to form a joint force to further improve its chiral recognition ability to better meet the needs of rapid separation of enantiomers,In order to protect food and drug food safety,and even the sustainable development of ecological environment services.This paper mainly includes five parts of the research work:The first part of the paper reviews various methods and basic principles of chiral resolution,and systematically summarizes the development course and advantages and disadvantages of several chiral stationary phases widely used high performance liquid chromatography.It focuses on the cyclodextrin stationary phase Related properties and research progress.At the same time,the development of ordered mesoporous materials SBA-15 as a chromatographic bond phase matrix is also discussed as a theoretical support for the research work.In the second to fifth parts,the aryl urea hydrogen-bonding ligands,ethylenediamine complexing agents and weakly ionized phenylboronic acid were introduced into the ?-cyclodextrin port,and bonded on ordered mesoporous SBA-15 silica gel.And the chiral stationary phases of three new varieties were prepared and characterized.Their basic chiral separation ability was investigated and used for the separation and analysis of chiral pesticide and drug enantiomers,and the experimental data were provided for practical application in the future.The part two preparated para-methylamino uramido derivatized of ?-CD-bonded SAB-15 stationary phase(UCDP).The structure and morphology of UCDP were confirmed by the means of by mass spectrometry,transmission electron microscopy and solid-state nuclear magnetic resonance(NMR),etc.First,the column was measured and then the ability of the new stationary phase to separate the nitroaniline isomers was evaluated.The results showed that the stationary phase had higher isomer separation selectivity,and the para-isomers was eluted latest cause it could enter deeper into the cyclodextrin cavity.The chiral chromatographic properties of UCDP were studied by using ten kinds of triazole fungicides.The results showed that the separation of triazole fungicides was excellent at room temperature with water and methanol or acetonitrile.The resolution of hexaconazole and flutriafol was reaching2.50 and 1.81,and the analysis time is short(<30 min).The influence of the composition of the mobile phase and the column temperature on the resolution was studied.The thermodynamic parameters were determined.The results show that the chiral separation is the result of enthalpy driving.The mechanism of UCDP on the chiral recognition of these crops was discussed by combining the chemical structure of triazole fungicide and stationary phase.The synergistic effect of the cavity of the?-cyclodextrin ligand on the solute,the hydrogen bonding of the port and the steric hindrance enhances the enantiomeric recognition ability of the triazole fungicide.In the third part of the paper,the ?-cyclodextrin chiral stationary phase(UCDP)was modified by further optimizing the mobile phase composition and ratio,column temperature and other chromatographic parameters.The resolution of flutriafol and hexaconazole enantiomers was 2.02 and 2.42 under the optimum conditions.The method can simultaneously detect two-component enantiomers with rapid analysis speed.The HPLC-MS method was used to monitor flutriafol and hexaconazole enantiomers in the four kinds of fruit and vegetable substrates by selective ion,and the pretreatment of fruit and vegetable samples was carried out by simple magnetic recovery technology.The method was improved by the method of QuEChERS.The linear correlation was good(r ? 0.999)in the range of 0.05 ~ 12.5 mg/L,and the detection limit was 0.01 mg/L,and the accuracy,precision and(The average recovery was 81.93% ~ 101.10%,RSD was 1.05% ~ 7.11%,n=5).This method is simple,rapid and accurate,which provides a new method for the analysis of pesticide enantiomers in fruits and vegetables.In the fourth part of the paper,ethylenediamine modified ?-cyclodextrin chiralstationary phase(EASP)was prepared and its structure was characterized.Atenolol is a commonly used chiral drug for the treatment of cardiovascular disease.Chiral separation of atenolol is usually very difficult.The introduction of ethylenediamine complexing agent at the port of ?-cyclodextrin is beneficial for chiral resolution.In this study,the polar organic model was used,the resolution of atenolol enantiomers was 1.72 by optimizing the operating conditions of methanol content,glacial acetic acid,triethylamine and column temperature in the eluant.The analysis time is within25 min.A new method for the detection of enantiomeric contents of atenolol drugs was established by high performance liquid chromatography(HPLC-FLD).The two enantiomers had good linear correlation in the range of 0.05 ~ 5.0 mg/L.The detection limit was 0.02 mg/L,the accuracy was high,the sensitivity was high and the analysis was rapid.A new method was provided for the target content monitoring and clinical related pharmacological and metabolic studies of atenolol enantiomer.In the fifth part,EDC was used as dehydrating agent,4-carboxyphenylboronic acid was dehydrated with ethylenediamine ?-cyclodextrin and bonded to SBA-15 silica gel to prepare a weakly substituted phenylboronic acid mono-cyclodextrin chiral stationary phase(PHBSP),the structure of the newly prepared stationary phase was characterized by IR,elemental analysis and thermogravimetric analysis.8flavonoids,12 ?-blockers and 6 triazole fungicides were chosed as analyte.Flavonoids compounds were enantioseparated successfully under RPC condition,the analysis time was 30 min,the resolution of the 2'-hydroxyflavanone reached 3.15.Some ?-blockers was successfully resolved,the resolution of atenolol reached 1.59,the analysis time was less than 15 min.Most triazole fungicides can be resolved,the resolution of hexaconazole is 1.96.The mechanism of PHBSP for the separation of these three chiral substances was discussed.The weakly ionized phenylboronic acid cyclodextrin had better selectivity to ionizable polar solutes,and derivatized weakly oxidized phenylboronic acid groups doesn't possess ion exchange interaction,which still applicable to the reverse phase chromatography mobile phase. |
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