Enhanced enzymatic reaction by aqueous two-phase systems using parallel-laminar flow in a double Y-branched microfluidic device
Enhanced enzymatic reaction by aqueous two-phase systems using parallel-laminar flow in a double Y-branched microfluidic device
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在双 Y 分支微流体装置中使用平行层流增强水两相系统的酶促反应
DOI：
10.1016/j.cej.2017.10.085
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发表时间：
2018-03-01
影响因子：
15.1
通讯作者：
Meng, Tao
中科院分区：
文献类型：
--
作者：
Meng, Shi-Xin;Xue, Long-Hui;Meng, Tao
虽然有一些报道显示，在大规模的生物转化中使用双水相系统（ATPS），但ATPS的工业应用仍然受到其缺点的阻碍，如扩散传质慢，相分离的沉降时间长，和间歇过程。在这里，我们首次提出了一个连续流过程的基础上，适当设计的ATPS平行层流在双Y分支微流控装置用于酶催化。在模型脲酶反应中，选择聚乙二醇（PEG）8kDa和葡聚糖（Dex）500kDa作为聚合物溶液，其中酶主要在Dex相中沉降，而产物在短停留时间内主要分配到PEG相。由于快速的微传输，以及集成一个单一的步骤的生物催化和分离过程，在这样的ATPS微流控平台中的酶催化的明显增强被证明。与烧杯中温和搅拌下的传统ATPS相比，ATPS微流控中的酶促反应速率高500倍。此外，流速，底物浓度，停留时间，和循环次数对反应速率和转化率的影响进行了评估，分别。本研究为酶催化过程强化提供了一个全水、微尺度、反应分离耦合的平台，不仅具有理论意义，而且对生物医学、制药、食品等以生物转化为基础的应用领域具有实用价值。
Although there are several reports showing the employment of aqueous two-phase systems (ATPS) for biotransformation in large-scale, the industrial application of ATPS is still hampered by their drawbacks such as slow diffusive mass transfer, long settling time for phase separation, and batch processes. Here, we propose for the first time a continuous-flow process based on a suitably designed ATPS parallel-laminar flow in a double Ybranched microfluidic device using for enzymatic catalysis. In a model urease reaction, polyethylene glycol (PEG) 8 kDa and dextran (Dex) 500 kDa are selected as polymer solutions, in which the enzymes settle mainly in the Dex phase while the products partition mainly to the PEG phase during short residence time. On account of rapid micro-transport, as well as integrate one single step of biocatalysis and separation process, obvious intensification of enzymatic catalysis in such ATPS microfluidic platform is demonstrated. Compared with the conventional ATPS in a beaker under gentle stirring, the enzymatic reaction rate in ATPS microfluidic is 500 times higher. Furthermore, the effects of flow rates, substrate concentration, residence time, and recycling number on the reaction rate and conversion rate are evaluated, respectively. Our study provides an all-aqueous, micro-scale and coupled reaction-separation platform for the process intensification of enzymatic catalysis, which has not only theoretical significance, but also practical value for biotransformation-based fields, such as biomedical, pharmaceuticals and food applications.