title: Filling polymersomes with polymers by peroxidase-catalyzed atom transfer radical polymerization.
abstract: Polymersomes that encapsulate a hydrophilic polymer are prepared by conducting biocatalytic atom transfer radical polymerization (ATRP) in these hollow nanostructures. To this end, ATRPase horseradish peroxidase (HRP) is encapsulated into vesicles self-assembled from poly(dimethylsiloxane)-block-poly(2-methyl-2-oxazoline) (PDMS-b-PMOXA) diblock copolymers. The vesicles are turned into nanoreactors by UV-induced permeabilization with a hydroxyalkyl phenone and used to polymerize poly(ethylene glycol) methyl ether acrylate (PEGA) by enzyme-catalyzed ATRP. As the membrane of the polymersomes is only permeable for the reagents of ATRP but not for macromolecules, the polymerization occurs inside of the vesicles and fills the polymersomes with poly(PEGA), as evidenced by (1) H NMR. Dynamic and static light scattering show that the vesicles transform from hollow spheres to filled spheres during polymerization. Transmission electron microscopy (TEM) and cryo-TEM imaging reveal that the polymersomes are stable under the reaction conditions. The polymer-filled nanoreactors mimic the membrane and cytosol of cells and can be useful tools to study enzymatic behavior in crowded macromolecular environments.
authors.affiliation: Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056, Basel, Switzerland.
authors.forename: Maria Valentina
authors.initials: MV
authors.lastname: Dinu
authors.forename: Mariana
authors.initials: M
authors.lastname: Spulber
authors.forename: Kasper
authors.initials: K
authors.lastname: Renggli
authors.forename: Dalin
authors.initials: D
authors.lastname: Wu
authors.forename: Christophe A
authors.initials: CA
authors.lastname: Monnier
authors.forename: Alke
authors.initials: A
authors.lastname: Petri-Fink
authors.forename: Nico
authors.initials: N
authors.lastname: Bruns
mesh_terms: D002384:Catalysis; D005609:Free Radicals / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry; D058105:Polymerization; D011108:Polymers / Q000737:chemistry
chemical_list: D005609:Free Radicals; D011108:Polymers; D006735:Horseradish Peroxidase
keywords: amphiphilic block copolymer vesicles; atom transfer radical polymerization (ATRP); bio-inspiration; biocatalysis; nanoreactors