| Chirality is so closely related with our daily life and health. With the rapiddevelopment of life science and pharmaceutical industry, the demand for opticallypure single enantiomer is dramatically increasing. The chiral separation is asignificant task because enantiomers have almost same properties, especiallyenantioseparation of chiral drugs. High performance liquid chromatography (HPLC)is one of the most common and effective analysis techniques of the enantioseparation.The chiral ligands are bonded to the silica matrix, which obtained chiral stationaryphase that is directly used for enantioseparation. This is current research hot spot ofchiral HPLC, which has the simple, quick and reproducible advantages. Cyclodextrinbonded chiral stationary phase is one of common stationary phases at present. Thehydroxy groups of cyclodextrin are derivatived by different reagents, which obtainedthe derivatived cyclodextrin chiral stationary phases. They expand effectivelyenantioseparation range and enhance chiral recognition ability. At the same time,they have significant meaning for perfecting method of quality control of the chiraldrugs enantiomers and relevant pharmacokinetic study.The p-nitrophenylcarbamoylated β-cyclodextrin bonded SBA-15chiralstationary phase (NPCSP),2,4-dinitrobenzene ether-β-cyclodextrin bonded SBA-15chiral stationary phase (NESP),6-mono-nitrophenylamino-β-cyclodextrin bondedSBA-15chiral stationary phase (NCDSP) and N,N’-ethylenediamino bridgedbis(β-cyclodextrin)-bonded SBA-15chiral stationary (BCDSP) were firstlysynthesized in this paper. And they all were used for study of separation of drugsenantiomers. The results show that they have the excellent chiral recognition andseparation effect. The bridged bis(β-cyclodextrin) with simulated enzyme functionwas used for preparation of stationary phase in this paper. And its function of chiralseparation is firstly developed, which is an innovative work. The main research workincludes the following five parts:The first part systematically and comprehensively summarizes all kinds of chiralchromatographic separation technologies, and the development situation of chiralstationary phases of high performance liquid chromatography at home and abroad inrecent years, among the development of cyclodextrin chiral stationary phases isreviewed in detail. And the development of ordered mesoporous material SBA-15as chromatographic matrix is reviewed, which takes them as the theory basis of thiswork.The p-nitrophenylcarbamoylated β-cyclodextrin bonded SBA-15chiralstationary phase (NPCSP) was synthesised by “Click Chemistry” reaction in thesecond part. And related structure characterization of NPCSP was accomplishedthrough scanning electron microscopy, transmission electron microscopy, infraredspectrum and element analysis. The enantioseparation performance of three kinds ofβ-blockers drugs(atenolol, metoprolol and esmolol) on NPCSP was studied under thepolar organic solvent mode. The resolutions of above three kinds of drugsenantiomers are respectively1.45,1.32and1.15under the optimized conditions. Andthe analysis time is10~30minutes, which is much shorter than the literatures. Themechanism of chiral separation of NPCSP was discussed based on the structuralfeature of β-blockers drugs. The results showed that the hydrogen-bonding interactionfrom port and inclusion interaction from cavity of β-cyclodextrin could enhance chiralrecognition ability to β-blockers, together with the column has excellent permeabilityand low mass transfer resistance by orderly SBA-15, which results in rapid chiralseparation results.The2,4-dinitrobenzene ether-β-cyclodextrin bonded SBA-15chiral stationaryphase (NESP) with stable ether-bonding was prepared through the “Click Chemistry”reaction in the third part. The characterization of structure and morphology of NESPwas accomplished through transmission electron microscopy, mass spectrometer,infrared spectrum, elemental analysis and thermogravimetric analysis. Theenantioseparation performance of NESP was systematically studied with four kinds ofcommon β-blockers as solute probes under polar organic solvent mode. The effects ofcomposition of mobile phase, temperature and flow rate on the enantioseparation ofβ-blockers were also investigated which took esmolol as example. The methanolcontent and ratio and content of triethylamine/glacial acetic acid in non-aqueousmobie phase were mainly studied. It could be found that methanol ashydrogen-bonding donor is added to the mobile phase, which will weakenhydrogen-bonding interaction between β-cyclodextrin ligand and solute. Thetriethylamine and glacial acetic acid could change the form of solute and peak shape.So they are the key factors in chiral separation. It is confirmed that the separation ofesmolol is enthalpy-controlled by the related thermodynamic parameters analysis, andthe lower column temperature is benefit for the above chiral separation.The6-mono-nitrophenylamino-β-cyclodextrin bonded SBA-15chiralstationary phase (NCDSP) was synthesized in the fourth part. And related structure characterization of NCDSP was accomplished through scanning electron microscopy,transmission electron microscopy, X-ray diffraction, specific surface area analyzers,mass spectrometer, infrared spectrum, elemental analysis and thermogravimetricanalysis. The basic chromatographic property of NCDSP was evaluated and used forenantioseparation of β-blockers and dihydroflavanones. The fourteen kinds ofβ-blockers and six kinds of dihydrflavanones chiral drugs could be separated onNCDSP. And the analysis time of the most of solutes were generally not more than20minutes. It could be found that the introduction of nitro of electron-attracting groupcould reduce the electronic density of benzene ring and the π-acid β-cyclodextrinligand has excellent chiral recognition ability to π-alkaline β-blockers drugs, whichcould separate wider chiral drugs by comparative study withphenylamino-β-cyclodextrin bonded SBA-15chiral stationary phase (PCDSP).The bridged bis(β-cyclodextrin) with simulated enzyme function was used forpreparation of stationary phase and the devolpment of its chiral separation in the fifthpart. The N,N’-ethylenediamino bridged bis(β-cyclodextrin)-bonded SBA-15chiralstationary (BCDSP) was synthesized. And related structural characterization ofBCDSP was accomplished through mass spectrometry, infrared spectroscopy,elemental analysis and thermogravimetric analysis. The influences of content oforganic solvent, modifiers of glacial acetic acid/triethylamine and temperature onenantioseparations were studied under polar organic solvent mode. The commonfourteen kinds of β-blockers are separated successfully, among them the resolutions ofpropranolol and carvediol were respectively2.18and2.01, and the analysis time werenot more than20minutes. The BCDSP exhibited good separation performance.However, the β-cyclodextrin-bonded chiral stationary phase with single cavity couldpartially separate only four β-blockers under the optimized conditions, and theresolutions were also less than those of BCDSP. Obviously, the synergisticinteractions of double β-cyclodextrin cavity could expand space recognition domain,also improved the stereoselectivity. So the BCDSP has a wider solute, a higherresolution and shorter analysis time. |
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