In situ entrapment of urease in cryogels of poly(N‐isopropylacrylamide): An effective strategy for noncovalent immobilization of enzymes
In situ entrapment of urease in cryogels of poly(N‐isopropylacrylamide): An effective strategy for noncovalent immobilization of enzymes
复制标题
聚（N-异丙基丙烯酰胺）冷冻凝胶中脲酶的原位捕获：酶非共价固定的有效策略
DOI：
10.1002/app.34063
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发表时间：
2011
影响因子：
3
通讯作者：
R. Dimkov
中科院分区：
文献类型：
--
作者：
P. Petrov;S. Pavlova;C. Tsvetanov;Y. Topalova;R. Dimkov
以过氧化氢为引发剂，采用紫外光辐照法制备了含脲酶的聚N-异丙基丙烯酰胺（PNIPAAm）超大孔冻凝胶。具体而言，由于冷冻结构化现象，尿素酶分子嵌入到致密的冷冻凝胶壁中。因此，尽管酶被物理截留，但由于在冷冻凝胶壁中形成的致密聚合物网络，该系统表现出显著的抗泄漏性。固定化脲酶在间歇和流动两种方式下都能在较宽的温度范围内催化尿素水解。互连的大孔有助于底物和反应产物通过凝胶的不受阻碍的扩散，因此，与常规的PNIPAAm水凝胶相比，为以恒定的活性连续重复使用铺平了道路。由于海绵状形态，含有尿素酶的PNIPAAm冻凝胶可以用作高渗透膜，用于从连续流动的进料溶液中直接除去痕量的尿素。© 2011 Wiley Periodicals，Inc.应用聚合物科学杂志，2011年
Supermacroporous poly(N-isopropylacrylamide) (PNIPAAm) cryogels containing urease were prepared via UV irradiation technique and hydrogen peroxide as initiator. Specifically, due to the cryostructuration phenomenon urease molecules were embedded into the dense cryogel walls. Thus, although the enzyme is physically entrapped, the system exhibited remarkable resistance against leaking due to the dense polymer network formed in the cryogel walls. The immobilized urease can catalyze the hydrolysis of urea in a broad temperature range in both batch and flow regime. The interconnected macropores assist for unhindered diffusion of the substrate and reaction products through the gel, thus, paving the way for consecutive reuse at a constant activity, in contrast to the conventional PNIPAAm hydrogel. Due to the spongy-like morphology PNIPAAm cryogels containing urease can be exploited as highly permeable membrane for direct removal of traces of urea from continuously flowing feed solutions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011