溶胶-凝胶法固定化酶的问题与解决途径

综述了溶胶-凝胶固定化酶由于凝胶化时间过长，凝胶孔径偏小以及凝胶机械强度低等问题的存在引起酶构象改变、屏蔽，底物与产物的扩散速率慢以及酶与底物的不易接触。并提出了相应的解决办法：选择适宜的前驱体及固定化条件可以缩短凝胶化时间；加入聚乙二醇改性剂、非表面活性剂模板剂可以调大凝胶的孔径；微波快速干燥。加入添加剂则可以提高凝胶的机械强度。同时也提出可以避免酶变性的其他一些途径，如对凝胶老化阶段的特殊处理，选择合适的缓冲液等。

Problems and Solutions of Enzyme Encapsulation through Sol-gel Process

The typical problems encountered in enzyme encapsulation through sol|gel proces s,such as too long gelation time,small gel pore size,low gel mechanical strength and so on, are briefly outlined.These problems can result in three dimensional conform ation alteration and the active site shielding of the immobilized enzyme,the slo w dif fusion rate and the inaccessibility of substrate to the immobilized enzyme.The c orresponding tentative solutions are presented herein:the gelation time can be c onsiderably shortened by the appropriate screening of precursors and encapsulati on conditions.The gel pore size can be enlarged and structure can be tailored wi th the introduction of chemical modifiers such as polyethylene glycol,glucose,cy clodextrin and other nonsurfactants.The mechanical strength of gel can be increa s ed by the suitable drying process and drying control additives.In addition,other approaches are also mentioned to avoid enzyme denaturation,such as the special treatment during the aging stage and the suitable selection of buffer solution.