Please use this identifier to cite or link to this item:
In this study, commercial regenerated cellulose membranes were modified with different chelating agents to prepare the immobilized metal affinity membranes. The relevant immobilized copper amounts and batch adsorption capacities of different proteins, lysozyme, γ-globulin and BSA, were measured and the effects of pH and salt concentration on adsorption were investigated. The results show that the use of IDA achieved both the largest immobilized amount of copper ions and the largest protein adsorption capacity. As to the pH effect, the protein adsorption was dominated mainly by the affinity binding when the pH values were lower than the pKa for deprotontation of histidine residue on protein molecule surface. On the other hand, at the pH values higher than the pKa, the electrostatic interaction between protein and the nonspecific binding sites on the membranes became significant, but it could be suppressed by adding an optional salt concentration in the solution (0.5 M in this work). For the batch adsorption of three-protein mixture, γ-globulin exhibited the greatest adsorption affinity, whereas lysozyme had the largest adsorption capacity. In the flow experiments, the three proteins could not be separated because all of them had affinities with the immobilized metal affinity membranes.
本研究以再生纖維素薄膜為固體載體，改質接上不同之螯合劑，探討其在不同pH值與鹽類濃度下，對於lysozyme、γ-globulin及BSA (bovine serum albumin)的吸附情形。在單一蛋白質的批式吸附部分，以IDA (iminodiacetic acid)為螯合劑所得之銅離子固定量與蛋白質吸附量均是四種螯合劑中最好的。當吸附環境的pH值改變從5.4提高至7.4時，飽和吸附量也隨著提高，顯示吸附受histidine氨基酸殘基上去質子化的親和配位鍵結力影響較大；而當pH值從7.4提高至9.4時，非特定吸附的靜電作用力對吸附效果影響增大。此外，以靜電吸引力為主之非特定性吸附現象可藉加入適當之鹽類濃度(約0.5 M KCl)來改善。在三蛋白質之吸附平衡實驗部分，γ-globulin的吸附力最強，而lysozyme之吸附量最大，均與單一蛋白質之情形相同。但流動吸附實驗之結果則顯示：此三蛋白質均會吸附，故無法有效分離。
|Appears in Collections:||化學工程學系所|
Show full item record
TAIR Related Article
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.