超大孔聚合物微球PGMA的亲水改性及其在分离纯化中的应用

发布时间：2018-10-05 13:43

【摘要】：超大孔聚合物PGMA微球具有疏水性,容易与蛋白发生非特异性吸附使其失去活性,且制备的微球载量较低。笔者针对这一问题进行如下探究:PGMA微球作为基材,在有机溶剂DMSO中通过环氧基在其表面接枝葡聚糖,然后通过烯丙基活化方法在碱溶液中多次镀层葡聚糖,使其表面含有大量亲水性基团OH,从而达到亲水改性的目的。然后通过红外光谱仪、扫描电镜和原子力显微镜对改性前后微球的化学组成和形貌进行表征;红外表征表明葡聚糖接枝到微球上,扫描电镜和原子力显微镜表明改性后微球形貌未发生改变;非特异性吸附结果表明,改性前后,其非特异性吸附由原来的60%左右变为2%左右,与亲水性的琼脂糖微球的非特异性吸附相近,接触角从153°降低到约为0°,亲水性良好。用亲水改性的PGMA微球通过环氧氯丙烷环氧活化连接耐碱ProteinA亲和配基,制备成亲和层析介质,并对其制备条件进行优化,对其载量和性能进行表征。扫描电镜和压力-流速曲线测试表明改性前后其流通性能变化不大。考察了环氧值、配基密度及载量之间的关系,结果表明配基密度随着环氧值的增大而增大、载量随着配基密度的增大先增大后减小,在配基密度为4.52 mg/mL时,其动态载量达到最大值,为16.1 mg/mL。考察其在不同保留时间下介质的动态载量,结果显示,随着保留时间从5 min缩短到1 min,介质的动态载量仅仅下降13%,表明其在快速分离纯化上有一定的潜力。用亲水改性的PGMA微球连接DEAE阴离子交换配基,制备成阴离子交换介质,并对其改性前后的形貌进行表征。结果表明,改性前后微球形貌未改变。并考察了孔径、配基密度对其动态载量的影响。结果表明,随着孔径的增大,载量变小,而随着配基密度的增加,介质的载量先增大后减小。还考察其在不同保留时间下介质的动态载量,结果显示,随着保留时间从5 min缩短到1 min,介质的动态载量仅仅下降18%,表明其在快速分离纯化上有一定的潜力。
[Abstract]:The macroporous polymer PGMA microspheres are hydrophobic and easily adsorbed with protein to make them lose their activity and the load of the prepared microspheres is low. In order to solve this problem, the author studied that the microspheres were grafted with dextran on the surface by epoxy group in organic solvent DMSO, and then coated with dextran in alkaline solution by allyl activation method. The hydrophilic modification can be achieved by making the surface containing a large number of hydrophilic groups OH,. Then the chemical composition and morphology of the microspheres before and after modification were characterized by infrared spectrometer, scanning electron microscope and atomic force microscope, and the results showed that dextran was grafted onto the microspheres. Scanning electron microscopy and atomic force microscope showed that the morphology of the modified microspheres did not change, and the nonspecific adsorption of the modified microspheres changed from about 60% to about 2% before and after the modification. The contact angle was reduced from 153 掳to about 0 掳, and the hydrophilicity was good. The hydrophilic modified PGMA microspheres were used to connect the alkali-resistant ProteinA affinity ligand with epichlorohydrin epoxy-activated. The hydrophilic and chromatographic media were prepared. The preparation conditions were optimized and the loading and properties of the ligands were characterized. Scanning electron microscopy and pressure-flow curve test showed that the fluidity of the modified material changed little before and after modification. The relationships among epoxide value, ligand density and loading capacity were investigated. The results showed that the ligand density increased with the increase of epoxy value, and the loading increased first and then decreased with the increase of ligand density. The ligand density was 4.52 mg/mL. Its dynamic load reached a maximum of 16.1 mg/mL.. The dynamic loading of the medium at different retention times was investigated. The results showed that the dynamic load of the medium decreased only by 13 with the retention time shortened from 5 min to 1 min, which indicated that it had a certain potential for rapid separation and purification. DEAE anion exchange ligands were connected with hydrophilic PGMA microspheres. Anion exchange media was prepared and its morphology was characterized before and after modification. The results showed that the morphology of the microspheres remained unchanged before and after modification. The effects of pore size and ligand density on the dynamic loading were investigated. The results show that the loading capacity decreases with the increase of pore size, and then decreases with the increase of ligand density. The dynamic load of the medium at different retention times was also investigated. The results showed that the dynamic load of the medium decreased only by 18% with the shortening of the retention time from 5 min to 1 min, indicating that it has a certain potential for rapid separation and purification.
【学位授予单位】：河北科技师范学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O631;O652.6

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