DEVELOPMENT OF COMPOSITE OF CHITOSAN AND DEXTRAN FOR SEPARATION OF PROTEINS AND ITS APPLICATION FOR INDUSTRIAL LARGE SCALE PROTEIN SEPARATION

离子交换色谱可用于大规模工业规模的蛋白质分离。已经开发了许多离子交换剂。葡聚糖-DEAE如DEAESephadex A-50（Pharmacia LKB Biotechnology）是非常好的蛋白质分离剂。然而，由于它是非常软的，它被压缩在一个柱，即使在非常缓慢的流速，因此它不能用于工业规模的蛋白质分离。在目前的工作中，我们已经开发了一种复合壳聚糖和葡聚糖-DEAE使葡聚糖-DEAE硬。右旋糖酐-DEAE的载体是壳聚糖珠，Chitopentadiene 2501（Ch-2501，Fuji Spinning Co.），它是一种硬凝胶，本身就是蛋白质的吸附剂。通过葡聚糖溶液与Ch-2501的接触，使葡聚糖渗透到Ch-2501的大孔中。此后，大孔中的葡聚糖交联，然后在葡聚糖网络上引入DEAE。成品（以下称为Ch-Dx-DEAE-2）较硬，根本未在色谱柱中压缩。平衡ISO ...更多信息 pH值对BSA的吸附温度影响较大。这表明Ch-Dx-DEAE-2用于蛋白质分离是可行的。等温线与Langmuir方程关联良好。Ch-Dx-DEAE-2对BSA的饱和吸附量分别是DEAESepharoseFastFlow（PharmaciaLKB Biotechnology）、Ch-2501和DEAESephadexA-50的4.5、2.5和1.3倍。实验穿透曲线与考虑颗粒内扩散、液膜扩散和床层轴向扩散的理论穿透曲线吻合较好。BSA的颗粒内有效扩散系数的测定通过匹配的实验穿透曲线与理论的。在上述离子交换剂中，Ch-Dx-DEAE-2的扩散系数最大。它比Ch-2501大十倍。吸附在Ch-Dx-DEAE-2上的牛血清白蛋白易于用NaCl水溶液解吸。BSA从吸附床层上的洗脱曲线非常尖锐，洗脱峰的峰值是吸附过程中BSA进料浓度的870倍。这比使用世界上常用的最好的商业离子交换剂获得的大4倍。少

Ion exchange chromatography is useful for large industrial-scale separation of proteins. A number of ion exchangers have been developed. Dextran-DEAE such as DEAE Sephadex A-50 (Pharmacia LKB Biotechnology) is a very good protein separator. However since it is very soft, it is compressed in a column even in very slow flow rate and therefore it can not be used in industrial-scale protein separation.In the present work, we have developed a composite of chitosan and dextran-DEAE to make the dextran-DEAE hard. The supporter of the dextran-DEAE was a chitosan bead, Chitopearl 2501 (Ch-2501, Fuji Spinning Co.), which was a hard gel and an adsorber of protein in itself. We let dextran penetrate into the macropores of Ch-2501 by contacting with dextran solution. Thereafter, the dextran in the macropore was cross-linked and then DEAE was introduced on the dextran network. The finished product (hereafter called Ch-Dx-DEAE-2) was hard and was not compressed in a column at all. The equilibrium iso … More therm for adsorption of BSA was affected by pH considerably. This means that Ch-Dx-DEAE-2 is feasible for separation of proteins. The isotherms were correlated well by the Langmuir equation. The saturation capacity for adsorption of BSA on Ch-Dx-DEAE-2 was 4.5,2.5, and 1.3 times larger than those of DEAE Sepharose Fast Flow (Pharmacia LKB Biotechnology), Ch-2501, and DEAE Sephadex A-50, respectively. The experimental breakthrough curve agreed well with the theoretical breakthrough curve obtained by considering the intraparticle diffusion, liquid film diffusion, and axial dispersion in the bed. The intraparticle effective diffusivities of BSA were determined by matching the experimental breakthrough curves with the theoretical ones. The diffusivity in Ch-Dx-DEAE-2 was the largest in the above ion exchangers. It was ten times larger than that in Ch-2501. BSA adsorbed on Ch-Dx-DEAE-2 could be desorbed using NaCl aqueous solution easily. The elution curve of BSA from the bed was very sharp.The value of the peak was 870 times larger than that of feed concentration of BSA in adsorption process. This is 4 times larger than that obtained using the best commercial ion exchanger which is used commonly in the world. Less