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Title: Continuous Curvature Change into Controllable and Responsive Onion-like Vesicles by Rigid Sphere−Rod Amphiphiles
We observe the formation of highly controllable and responsive onion-like vesicles by using rigid sphere−rod amphiphilic hybrid macromolecules, composed of charged, hydrophilic Keggintype clusters (spheres) and hydrophobic rod-like oligofluorenes (OFs). Unlike the commonly used approach, which mainly relies on chain bending of flexible molecules to satisfy different curvatures in onion-like vesicles, the rigid hybrids form flexible interdigitations by tuning the angles between OFs, leading to the formation of bilayers with different sizes. The self-assembled vesicles possess complete onion-like structures from most inner to outer layers, and their size (layer number) can be accurately manipulated by different solution conditions including solvent polarity, ionic strength, temperature, and hybrid concentration, with fixed interbilayer distance under all conditions. Moreover, the vesicle size (layer number) shows excellent reversibility to the change of temperature. The charged feature of spheres, rod length, and overall hybrid architecture shows significant effects on the formation of such onion-like vesicles.  more » « less
Award ID(s):
1665284
PAR ID:
10187246
Author(s) / Creator(s):
Date Published:
Journal Name:
ACS nano
Volume:
14
ISSN:
1936-086X
Page Range / eLocation ID:
1811-1822
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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