Preparation Of Macroporous Cyclodextrin Matrix And Its Application In Purification Of Soy Isoflavones

Chromatography is widely used in separation and purification. Matrix is one of the key factors, which affect the efficiency of mass transfer and separation. Cyclodextrin is hydrophobic inside and hydrophilic outside. The hydrophilic hydroxyl groups can be chemically modified into functional derivatives, while the hydrophobic cavity can form inclusion complexes with different molecules, such as isoflavones. Moreover, the cavity is preserved after polymerization. So cyclodextrin polymer has been focused on environmental protection, medicine, food and chromatography. This thesis focuses on the preparation, properties and application of cyclodextrin medium. We choose the best medium by comparing the adsorption properties of different media to apply in soy isoflavones’s purification.Firstly, we prepared a series of CDP beads after the process of dissolution, cross-linking, reversed phase suspension and solidification by controlling the amount of CaCO3(TuC). The preparation conditions were examined, including stirring speed and CaCO3. The properties of CDP beads were also characterized. It was found that, the beads with good sphericity followed the logarithmic normal size distribution, and the mean diameter was bellow200μm. The macroporous beads (M-CDP) were larger than the homogeneous beads (H-CDP). The water content, porosity and pore volume of M-CDP were higher than the H-CDP, indicated that CaCO3can enlarge pores in the beads.Secondly, rutin was adsorbed by CDP beads in aqueous solution. The static adsorption, dynamic adsorption and penetration behavior and the factors affecting adsorption were studied. The adsorption behavior followed the Langmuir adsorption equation, and the adsorption capacity of M-CDP was larger than H-CDP and CD-TuC. The capacity decreased as the temperature and pH of solution rise. The pore diffusivity of M-CDP was about three times as big as H-CDP and CD-TuC. The dynamic adsorption capacity of M-CDP was bigger than that of H-CDP and CD-TuC.Thirdly, the practical application of CD-Ca3medium was carried out in an fixed bed for purifying soy isoflavones. The feedstock from crude soy isoflavones was loaded onto CD-Ca3in a fixed bed after pretreatment. After being washed with water, the isoflavones were eluted with ethanol from the bed. The recovery ratio was87.11%with the isoflavones purity of93.39%. The results demonstrate that CD-Ca3is suitable for isoflavonoids separation and purification. It is expected that the novel medium CD-Ca3would be a promising candidate for isoflavonoids separation and purification.