Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576, Singapore.
Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576, Singapore.
J Colloid Interface Sci. 2014 Aug 15;428:146-51. doi: 10.1016/j.jcis.2014.04.033. Epub 2014 Apr 30.
Uniform cross-linked cellulase aggregate (XCA) can be prepared by using a millifluidic reactor which consists of two inlets and a Y-junction, because mixing pattern and spatial distribution of reactants can be controlled precisely.
Aqueous cellulase solution is mixed with acetonitrile (as a precipitant) and 20 mM of glutaraldehyde (as a cross-linker) at the Y-junction. XCA is collected from the outlet of the reactor.
Uniform XCA, with an average size between 200 nm and 400 nm, can be formed inside the reactor. Unlike free cellulase, XCA is insoluble such that it can be filtered out from the solution. It can be used alone or absorb on silica gel (XCA-Si) as a catalyst for hydrolyzing carboxymethyl cellulose (CMC). Interestingly, XCA-Si shows highest activity at pH 4.8 and 50°C, which is similar to the optimal condition of free cellulase. Moreover, XCA-Si is more stable than free cellulase at high temperature (>60°C). It precipitates naturally and can be recycled at least 5 times after the hydrolysis of CMC.
均一交联纤维素酶聚集体(XCA)可以通过使用由两个入口和一个 Y 型接头组成的微流控反应器来制备,因为反应物的混合模式和空间分布可以得到精确控制。
在 Y 型接头处,将水相纤维素酶溶液与乙腈(作为沉淀剂)和 20mM 戊二醛(作为交联剂)混合。从反应器的出口收集 XCA。
在反应器内部可以形成平均尺寸在 200nm 到 400nm 之间的均一 XCA。与游离纤维素酶不同,XCA 不溶于水,因此可以从溶液中过滤出来。它可以单独使用,也可以吸附在硅胶(XCA-Si)上作为水解羧甲基纤维素(CMC)的催化剂。有趣的是,XCA-Si 在 pH4.8 和 50°C 时表现出最高的活性,与游离纤维素酶的最佳条件相似。此外,XCA-Si 在高温(>60°C)下比游离纤维素酶更稳定。它自然沉淀,可以在水解 CMC 后至少回收 5 次。