Premium
Recognition‐Induced Polymersomes: Structure and Mechanism of Formation
Author(s) -
Uzun Oktay,
Xu Hao,
Jeoung Eunhee,
Thibault Raymond J.,
Rotello Vincent M.
Publication year - 2005
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200500809
Subject(s) - polymersome , vesicle , polymer , polystyrene , bilayer , microscopy , materials science , mica , atomic force microscopy , x ray photoelectron spectroscopy , optical microscope , membrane , chemistry , chemical engineering , copolymer , nanotechnology , optics , amphiphile , scanning electron microscope , composite material , physics , biochemistry , engineering
Random polystyrene copolymers grafted with complementary recognition elements were combined in chloroform producing vesicular aggregates, that is, recognition‐induced polymersomes (RIPs). Reflection interference contrast microscopy (RICM) in solution, coupled with optical microscopy (OM) and atomic force microscopy (AFM) on solid substrates, were used to determine the wall thickness of the RIPs. Rather than a conventional mono‐ or bilayer structure (∼10 or ∼20 nm, respectively) the RIP membrane was 43±7 nm thick. Structural arrangement of the polymer chains on the RIP wall were characterized by using angle‐resolved X‐ray photoelectron spectroscopy (AR‐XPS). The interior portion of the vesicle membrane was found to be more polar, containing more recognition units, than the exterior part. This gradient suggests that a rapid self‐sorting of polymers takes place during the formation of RIPs, providing the likely mechanism for vesicle self‐assembly.