Separation Of Cephalosporin Antibiotics By Bis [6-O-(3-deoxy Citric Acid Monoester-4)]-β-cyclodextrin Chiral HPLC Mobile Phase Additives

Chiral pharmacokinetics of drugs and the demand for separation and analysis ofchiral drugs makes enantiomeric separation meaningful. This topic use chiral HPLCmobile phase additives to separation cephalosporins drug enantiomers. Study the impacton the separation from chiral mobile phase ratio, acidity, concentration. And also toexplore the mechanism of chiral separation. The main contents are:1.By analogy Chiral separation of enantiomers methods and tools, the paper overthe past decade chiral HPLC mobile phase additive categories and Chiral Separation andresearch background are briefly reviewed.2.Bis-[-6-O-(3-deoxy citric monoester-4)]-β-cyclodextrin (β-CD-B2) as a newmobile phase additives is used in HPLC Chiral cephalosporin antibiotics. The mobilephase additive was used to simulate the field of enzyme catalysis or inhibition. It is firstapplied to Chiral HPLC. This β-CD-B2derivatives, simple preparation, the solubilityand stereoselectivity of β-CD is larger extent improved in aqueous solution. Thehydroxyl groups of β-CD are replaced by carboxyl groups. There are better inclusionassociations between cyclodextrin and various guest molecules. The acidity and polarityof β-CD-B2derivatives is enhanced. It is easy formed the effect of the amino-containingalkaline chiral drug enantiomers. There are richer interaction sites, such as hydrogenbonding and π-π conjugation between this multi-substituted carboxyl derivative andβ-lactam antibiotics. β-CD-B2as a new mobile phase additives is dissolved in water. Itis organic weak acid solution, adding organic weak base, a stable solution oftriethylamine buffer system can be formed, without due plus buffered saline solutioncontrol the acidity.The interaction of mobile phase additives β-CD-B2and drug enantiomers inresolution mechanism is discussed. In order to verify the successful preparation of thetarget product, its spectrum of UV, FTIR spectra, XRD patterns and NMR-13C spectraare analysed.3.The novel chiral mobile phase additive β-CD-B2is used to chiral separationcephalosporin drugs in HPLC. The solubility of β-CD-B2additives and thephysicochemical properties of this additive are clarified, an buffer system with the weakorganic base is formed. The solubility of buffer in the organic solvent is investigated,thereby a new type of additive buffer-acetonitrile chiral mobile phase system isestablished.Application of this β-CD-B2in HPLC mobile phase additive system chiral separation cephalosporins antibiotic drugs series are cephalexin, ceftriaxone, cefdinir,cefuroxime and so on. By comparative experiments (β-cyclodextrin species of mobilephase additives), experimental conditions (Ratio between the constituent the chiralmobile phase additives, pH, concentration ofβ-CD-B2, etc.) and resolution mechanismare discussed. A series of cephalosporin antibiotics enantiomeric separation methods arecreated. The results show that the volume fraction of the mobile phase additive reached80%,3mmol/L chiral-acetonitrile mobile phase, pH7.0, it is the optimum conditions ofcefuroxime chiral separation. The degree of separation Rs reaches2.14. theconcentration of Cefuroxime is3.36×10-5mol/L~6.12×10-4mol/L range, there are alinear relationship between peak height, peak area with concentration, the linearcorrelation coefficient r=0.9967~0.9994. the relative standard deviation RSD (n=5)of each parameter are under3.75%. the former peak height-concentration standardcurve equation, linear correlation coefficient r=0.9967, peak area-concentrationstandard curve equation, linear correlation coefficient r=0.9994; the after peakhigh-concentration standard curve equation, linear correlation coefficient r=0.9886, thepeak area-concentration standard curve equation, linear correlation coefficient r=0.9994. Ceftriaxone: Vacetonitrile: Vadditives buffer=25%:75%, pH9.1, beta-CD-B2concentration is3mmol/L, the detection wavelength is310nm, flow rate:0.6ml/min,two enantiomers of ceftriaxone are baseline separated, the maximum resulution Rs is5.63. On cefdinir: at Vacetonitrile: Vadditives buffer=20%:80%, pH8.6, β-CD-B2concentration6mmol/L, the detection wavelength284nm, flow rate:0.8ml/min, thebaseline separatation of cefdinir two antipodes is attained. Of Cephalexin: at Vacetonitrile:VAdditives buffer=20%:80%, pH8.8, concentration ofβ-CD-B2is5mmol/L, the detectionwavelength310nm, flow rate:0.6ml/min, the baseline separatation of Cefalexin fourenantiomers are attained. Optimal conditions of4peak separation between adjacent twopeaks Rs are3.41,5.34and8.93.