Redox- and pH-Responsive Polymersomes with Ferrocene Moieties Exhibiting Peroxidase-like, Chemoenzymatic Activity and H<sub>2</sub>O<sub>2</sub>-Responsive Release Behavior
Sílvia Moreno, Hanna Hübner, Christiane Effenberg, Susanne Boye, Anthony R. Ramuglia, Deborah Schmitt, Brigitte Voit, Inez M. Weidinger, Markus Gallei, Dietmar Appelhans
Abstract
The development of compartments for the design of cascade reactions in a local space requires a selective spatiotemporal control. The combination of enzyme-loaded polymersomes with enzymelike units shows a great potential in further refining the diffusion barrier and the type of reactions in nanoreactors. Herein, pH-responsive and ferrocene-containing block copolymers were synthesized to realize pH-stable and multiresponsive polymersomes. Permeable membrane, peroxidase-like behavior induced by the redox-responsive ferrocene moieties and release properties were validated using cyclovoltammetry, dye TMB assay, and rupture of host-guest interactions with β-cyclodextrin, respectively. Due to the incorporation of different block copolymers, the membrane permeability of glucose oxidase-loaded polymersomes was changed by increasing extracellular glucose concentration and in TMB assay, allowing for the chemoenzymatic cascade reaction. This study presents a potent synthetic, multiresponsive nanoreactor platform with tunable (e.g., redox-responsive) membrane properties for potential application in therapeutics.