Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU- Dortmund, Emil-Figge-Strasse 66, 44227 Dortmund, Germany.
Langmuir. 2010 Jun 1;26(11):9152-9. doi: 10.1021/la9048727.
Multiphase flow microreactors benefit from rapid mixing and high mass transfer rates, yet their application in enzymatic catalysis is limited due to the fast inactivation of enzymes used as biocatalysts. Enzyme inactivation during segment flow is due to the large interfacial area between aqueous and organic phases. The Peclet number of the system points to strong convective forces within the segments, and this results in rapid deactivation of the enzyme depending on segment length and flow rate. Addition of surfactant to the aqueous phase or enzyme immobilization prevents the biocatalyst from direct contact with the interface and thus stabilizes the enzyme activity. Almost 100% enzyme activity can be recovered compared to 45% without any enzyme or medium modification. Drop tensiometry measurements point to a mixed enzyme-surfactant interfacial adsorption, and above a certain concentration, the surfactant forms a protective layer between the interface and the biocatalyst in the aqueous compartments. Theoretical models were used to compare adsorption kinetics of the protein to the interface in the segment flow microreactor and in the drop tensiometry measurements. This study is the basis for the development of segment flow microreactors as a tool to perform productive enzymatic catalysis.
多相流微反应器得益于快速混合和高传质速率，但由于用作生物催化剂的酶快速失活，其在酶催化中的应用受到限制。在分段流中，酶的失活是由于水相和有机相之间的大界面面积。系统的 Peclet 数表明在段内存在强对流力，这导致酶根据段长和流速快速失活。在水相或酶固定化中添加表面活性剂可防止生物催化剂与界面直接接触，从而稳定酶活性。与未经任何酶或介质修饰的酶相比，几乎可以回收 100%的酶活性。液滴张力测量表明存在混合酶-表面活性剂界面吸附，并且在某一浓度以上，表面活性剂在界面和水相之间的生物催化剂之间形成保护层。理论模型用于比较蛋白质在分段流微反应器中的界面吸附动力学和液滴张力测量中的界面吸附动力学。这项研究是开发分段流微反应器作为进行高效酶催化的工具的基础。
