Self-Assembly of Amphiphilic Block Copolypeptoids – Micelles, Worms and Polymersomes

Abstract

Polypeptoids are an old but recently rediscovered polymer class with interesting synthetic, physico-chemical and biological characteristics. Here, we introduce new aromatic monomers, N-benzyl glycine N-carboxyanhydride and N-phenethyl glycine N-carboxyanhydride and their block copolymers with the hydrophilic polysarcosine. We compare their self-assembly in water and aqueous buffer with the self-assembly of amphiphilic block copolypeptoids with aliphatic side chains. The aggregates in water were investigated by dynamic light scattering and electron microscopy. We found a variety of morphologies, which were influenced by the polymer structure as well as by the preparation method. Overall, we found polymersomes, worm-like micelles and oligo-lamellar morphologies as well as some less defined aggregates of interconnected worms and vesicles. Such, this contribution may serve as a starting point for a more detailed investigation of the self-assembly behavior of the rich class of polypeptoids and for a better understanding between the differences in the aggregation behavior of non-uniform polypeptoids and uniform peptoids.

Design and preparation of organic nanomaterials using self‐assembled peptoids

“…Using different methods, peptoids formed mainly (F) vesicles (by film rehydration method) or (G) worm‐like structure (by solvent switch method) (Adapted from Ref. under CC BY). H, Scheme of micellar forming peptoids 7 to 9 with anionic residues at different positions and cartoon of the nanostructures showing the position of the anionic monomers in blue (Adapted with permission from Ref.…”

“…Using a thin film hydration method, all the peptoids were able to form vesicles as shown by confocal microscopy, transmission electron microscopy (TEM) and dynamic light scattering (DLS) (Figure C,D). Using a similar approach, the Luxenhofer group synthesized amphiphilic block peptoids by nucleophilic living ring‐opening polymerization . These peptoids were composed of polysarcosine, the hydrophilic domain, and polypeptoids bearing short alkyl chains (from two to five carbon long) or aromatic groups, the hydrophobic block.…”

Linking two worlds in polymer chemistry: The influence of block uniformity and dispersity in amphiphilic block copolypeptoids on their self‐assembly

“…This circumstance led researchers to focus their synthesis and investigations on polymers containing blocks of the same monomer unit, mainly homopolymers or amphiphilic block copolymers. In contrast to uniform peptoids, the forming self‐assemblies of those polymeric systems in aqueous solutions are mostly limited to micelles, polymersomes, or related structures . Interesting exceptions are nanofibers and nanosheets derived from disperse block copolypeptoids …”

PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide‐Based Polymersomes

“…On the other hand, they prepared glycopeptide‐based polymersomes by ring‐opening polymerization and postpolymerization functionalization via click reaction . Polypeptoid‐based polymersomes have been investigated by Luxenhofer and co‐workers . Polypept(o)ide‐based polymersomes have been first reported by Kimura and co‐workers already in the late 1990s .…”