一种球形纤维素/钛白粉扩张床吸附剂的研究——组成对性能的影响

A SPHERICAL CELLULOSE/TiO_2 ADSORBENT FOR EXPANDED BED ADSORPTION——EFFECTS OF COMPOSITION ON PROPERTIES

采用反相悬浮再生法 ,以超细钛白粉颗粒作增重剂 ,包埋于纤维素骨架之中 ,经环氧氯丙烷活化后与二乙胺连接 ,制得一种球形扩张床吸附剂 .研究表明 ,吸附剂的密度、机械强度和孔结构可以随钛白粉用量的变化而改变 ;钛白粉颗粒的掺入有利于基质的活化 ,活化后环氧基含量可达 2 2 0 μmol mL .吸附剂具有良好的扩张床性能 ,扩张床中的蛋白质吸附行为与填充床中相似 ,吸附容量为 4 8 9mg牛血清白蛋白

Expanded bed adsorption (EBA) is a novel bioseparation technique,whic h integrates solid liquid separation,clarification,and initial purification i n to a single unit.One of the key points in EBA processes is the choice of a suit able matrix.In this paper,a new type of spherical cellulose TiO 2 composite mat rix for EBA was prepared through the method of water in oil suspension thermal r egeneration.After activated by epichlorohydrin and attached with diethylamine, the matrix was derivated to function as an anion exchanger for EBA.The effects of the contents of TiO 2 and cellulose in matrix on its properties were investi ga ted in details.It was found that TiO 2 not only acted as a densifier to impart a n increased density to the matrix,but also benefited the activation reaction by ep ichlorohydrin,giving the activated matrix an epoxy group content of 220 μmol/mL adsorbent.The prepared adsorbent showed a favorable expanded bed performance and could be used with higher linear velocity than that of the commercial Strea mline DEAE.The similar protein adsorption behavior both in expanded bed and in p acked bed was found with the maximum dynamic adsorption capacity of 48.9 mg bovi ne serum albumin (BSA)/mL adsorbent.The results indicate the custom made adsor bent can be applied to the expanded bed adsorption of proteins.