Self-assembled photoresponsive amphiphilic diphenylaminofluorene-C60 conjugate vesicles in aqueous solution
Sarika Verma1, Tanya Hauck, Mohamed E El-Khouly
1Department of Chemistry, Institute of Nanoscience and Engineering, University of Massachusetts, Lowell, Massachusetts 01854, USA.
Abstract:
Water-soluble oligo(ethylene glycolated) derivatives of two-photon absorptive diphenylaminofluorenocarbonyl-methano[60]fullerene, denoted as C60(>DPAF-EG6), were synthesized with their molecular self-assembly characteristics in H2O studied. The formation of nano- to submicron-sized spherical hollow vesicles with a shell width of 15-20 nm was observed by transmission electron microscopy (TEM) micrographs. This shell width fits approximately with the length of a disordered bilayer-like molecular packing of C60(>DPAF-EG6), arising from strong intermolecular hydrophobic interactions of fullerene cages. Photoinduced intramolecular charge separation followed by charge recombination on the nanosecond time scale, from the DPAF moiety to the C60 cage in the vesicle structure, was detected via transient spectroscopic measurements.
