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

• Applicant: Changzhu Wu, Ph.D.
• Subject Area: Polymer Materials ; Biological Process Engineering ; Synthesis and Properties of Functional Materials
• Term: from 2015 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 277012812

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.

• DFG Programme: Research Grants
• Co-Investigators: Professor Dr. Rainer Haag; Professorin Dr. Regine von Klitzing