Self-Sorting and Coassembly of Fluorinated, Hydrogenated, and Hybrid Janus Dendrimers into Dendrimersomes
journal contribution
posted on 2016-08-31, 00:00 authored by Qi Xiao, Jack D. Rubien, Zhichun Wang, Ellen
H. Reed, Daniel A. Hammer, Dipankar Sahoo, Paul A. Heiney, Srujana
S. Yadavalli, Mark Goulian, Samantha E. Wilner, Tobias Baumgart, Sergei A. Vinogradov, Michael L. Klein, Virgil PercecThe modular synthesis
of a library containing seven self-assembling
amphiphilic Janus dendrimers is reported. Three of these molecules
contain environmentally friendly chiral-racemic fluorinated dendrons
in their hydrophobic part (<b>R</b><sub><b>F</b></sub>), one contains achiral hydrogenated dendrons (<b>R</b><sub><b>H</b></sub>), while one denoted hybrid Janus dendrimer,
contains a combination of chiral-racemic fluorinated and achiral hydrogenated
dendrons (<b>R</b><sub><b>HF</b></sub>) in its hydrophobic
part. Two Janus dendrimers contain either chiral-racemic fluorinated
dendrons and a green fluorescent dye conjugated to its hydrophilic
part (<b>R</b><sub><b>F</b></sub><b>-NBD</b>) or
achiral hydrogenated and a red fluorescent dye in its hydrophilic
part (<b>R</b><sub><b>H</b></sub><b>-RhB</b>). These <b>R</b><sub><b>F</b></sub>, <b>R</b><sub><b>H</b></sub>, and <b>R</b><sub><b>H</b>F</sub> Janus dendrimers
self-assembled into unilamellar or onion-like soft vesicular dendrimersomes
(DSs), with similar thicknesses to biological membranes by simple
injection from ethanol solution into water or buffer. Since <b>R</b><sub><b>F</b></sub> and <b>R</b><sub><b>H</b></sub> dendrons are not miscible, <b>R</b><sub><b>F</b></sub><b>-NBD</b> and <b>R</b><sub><b>H</b></sub><b>-RhB</b> were employed to investigate by fluorescence microscopy
the self-sorting and coassembly of <b>R</b><sub><b>F</b></sub> and <b>R</b><sub><b>H</b></sub> as well as of
phospholipids into hybrid DSs mediated by the hybrid hydrogenated-fluorinated <b>R</b><sub><b>HF</b></sub> Janus dendrimer. The hybrid <b>R</b><sub><b>HF</b></sub> Janus dendrimer coassembled with
both <b>R</b><sub><b>F</b></sub> and <b>R</b><sub><b>H</b></sub>. Three-component hybrid DSs containing <b>R</b><sub><b>H</b></sub>, <b>R</b><sub><b>F</b></sub>, and <b>R</b><sub><b>HF</b></sub> were formed
when the proportion of <b>R</b><sub><b>HF</b></sub> was
higher than 40%. With low concentration of <b>R</b><sub><b>HF</b></sub> and in its absence, <b>R</b><sub><b>H</b></sub> and <b>R</b><sub><b>F</b></sub> self-sorted into
individual <b>R</b><sub><b>H</b></sub> or <b>R</b><sub><b>F</b></sub> DSs. Phospholipids were also coassembled
with hybrid <b>R</b><sub><b>HF</b></sub> Janus dendrimers.
The simple synthesis and self-assembly of DSs and hybrid DSs, their
similar thickness with biological membranes and their imaging by fluorescence
and <sup>19</sup>F-MRI make them important tools for synthetic biology.
