Self-Sorting and Coassembly of Fluorinated, Hydrogenated, and Hybrid Janus Dendrimers into Dendrimersomes
The 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 (RF), one contains achiral hydrogenated dendrons (RH), while one denoted hybrid Janus dendrimer, contains a combination of chiral-racemic fluorinated and achiral hydrogenated dendrons (RHF) in its hydrophobic part. Two Janus dendrimers contain either chiral-racemic fluorinated dendrons and a green fluorescent dye conjugated to its hydrophilic part (RF-NBD) or achiral hydrogenated and a red fluorescent dye in its hydrophilic part (RH-RhB). These RF, RH, and RHF 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 RF and RH dendrons are not miscible, RF-NBD and RH-RhB were employed to investigate by fluorescence microscopy the self-sorting and coassembly of RF and RH as well as of phospholipids into hybrid DSs mediated by the hybrid hydrogenated-fluorinated RHF Janus dendrimer. The hybrid RHF Janus dendrimer coassembled with both RF and RH. Three-component hybrid DSs containing RH, RF, and RHF were formed when the proportion of RHF was higher than 40%. With low concentration of RHF and in its absence, RH and RF self-sorted into individual RH or RF DSs. Phospholipids were also coassembled with hybrid RHF 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 19F-MRI make them important tools for synthetic biology.