Polymeric Core-shell Architectures to Adapt Biocatalytically Active Enzymes in Non-aqueous Media with Enhanced Performance

该项目旨在构建由亲水内部和疏水外壳组成的聚合核壳纳米颗粒，用于封装功能酶，并随后将其转移到具有增强催化性能的有机介质中。为此，一方面，我将逐步建立这个系统——从建立一个稳定的聚合物外壳到形成一个机械强度高、生物相容的核心基质。壳层将由合成嵌段共聚物形成，形成油包水（w/o）乳液，随后进行交联，届时将了解壳层稳定性与聚合物性能的相关性。内部核心网络将进一步生成生物相容性材料，以稳定酶并提高整个基质的机械强度。另一方面，在项目的所有阶段，我将反复评估和优化系统，以提高酶的性能（例如酶的活性、稳定性和可重用性），使用来自不同的合成重要类别的三种酶，即来自南极假单胞菌的脂肪酶B （CalB）、来自荧光假单胞菌的苯甲醛裂解酶（BAL）和来自假单胞菌的羰基还原酶（CPCR2）。通过这样的优化，最终通过对核壳平台的聚合物疏水性和微环境生物相容性的定制设计，为提高溶剂中的生物催化能力提供一般知识。此外，该系统将用不同的显微镜进行物理表征，并通过酶动力学进行定量评估，这可以进一步帮助我们了解载体性质（例如大小，膨胀行为和物质沉淀）与催化过程中传质的相关性。作为最终目标，我将应用最优的核壳胶囊来证明其在溶剂中酶合成手性化合物的可能性，希望通过合理设计聚合物网络的包封酶在不对称合成领域引起更多的兴趣。

The project aims at the construction of polymeric core-shell nanoparticles that consist of a hydrophilic interior and a hydrophobic shell for the encapsulation of functional enzymes as well as subsequent transferring them into organic media with enhanced catalytic performance. For this purpose, on one hand, I will stepwise build up the system - from the establishment of a stable polymer shell to the formation of a mechanically strong and biologically compatible core matrix. The shell will be formed by synthetic block copolymers for the formation of water-in-oil (w/o) emulsions and subsequent cross-linking, where the correlation of shell stability to polymer properties will be learned. The interior core networks will be further generated with biocompatible materials in order to stabilize enzymes and improve the mechanical strength of the whole matrix. On the other hand, I will repeatedly evaluate and optimize the system towards the enhanced enzymatic performance (e.g. enzyme activity, stability, and reusability) using three enzymes from distinct, synthetically important classes, namely lipase B from Candida antarctica (CalB), benzaldehyde lyase from Pseudomonas fluorescens (BAL), and carbonyl reductase from Candida parapsilosis (CPCR2) - at all stages of the project. With such optimization, general knowledge shall be finally provided to improve biocatalysis in solvents by the tailored design of the polymeric hydrophobicity and microenvironmental biocompatibility of core-shell platform. Furthermore, the system will be physically characterized with diverse microscopes and quantitatively assessed by enzyme kinetics, which can further help us get insights into the relevance of carrier properties (e.g. sizes, swelling behavior, and substance precipitation) to the mass transfer during catalysis. As an ultimate goal, I will apply the optimal core-shell capsules to demonstrate its possibility for enzymatic synthesis of chiral compounds in solvents, in hopes to arise more interests in the field of asymmetric synthesis by the encapsulated enzymes with rational design of polymeric networks.