PUB - Publikationen an der Universität Bielefeld

A sugar-functionalized water-soluble tribenzotriquinacene derivative bearing six glucose residues, TBTQ-(OG)(6), was synthesized and its interaction with C-60 and C-70-fullerene in co-organic solvents and aqueous solution was investigated by fluorescence spectroscopy and ultraviolet-visible spectroscopy. The association stoichiometry of the complexes TBTQ-(OG)(6) with C60 and TBTQ(OG)(6) with C-70 was found to be 1:1 with binding constants of K-a = (1.50 +/- 0.10) x 10(5) M-1 and K-a = (2.20 +/- 0.16) x 10(5) M-1, respectively. The binding affinity between TBTQ-(OG)(6) and C-60 was further verified by Raman spectroscopy. The geometry of the complex of TBTQ-(OG)(6) with C-60 deduced from DFT calculations indicates that the driving force of the complexation is mainly due to the hydrophobic effect and to host-guest pi-pi interactions. Hydrophobic surface simulations showed that TBTQ-(OG)(6) and C-60 forms an amphiphilic supramolecular host-guest complex, which further assembles to microspheres with diameters of 0.3-3.5 mu m, as determined by scanning electron microscopy.