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In the present work, we report the successful synthesis and characterization of six (two new) fullerene mono- and di-pyrene derivatives based on C60 and C70 fullerenes. The synthesized compounds were characterized by spectral methods (ESI-MS, 1H-NMR, 13C-NMR, UV-Vis, FT-IR, photoluminescence and photocurrent spectroscopy). The energy of HOMO and LUMO levels and the band gaps were determined from cyclic voltammetry and compared with the theoretical values calculated according to the DFT/B3LYP/6-31G(d) and DFT/PBE/6-311G(d,p) approach for fully optimized molecular structures at the DFT/B3LYP/6-31G(d) level. Efficiency of solar cells made of PTB7: C60 and C70 fullerene pyrene derivatives were analyzed based on the determined energy levels of the HOMO and LUMO orbitals of the derivatives as well as the extensive spectral results of fullerene derivatives and their mixtures with PTB7. As a result, we found that the electronic and spectral properties, on which the efficiency of a photovoltaic cell is believed to depend, slightly changes with the number and type of pyrene substituents on the fullerene core. The efficiency of constructed solar cells largely depends on the homogeneity of the photovoltaic layer, which, in turn, is a derivative of the solubility of fullerene derivatives in the solvent used to apply these layers by spincoating.

A series of thioacetyl-functionalized fullerene-C 60 derivatives were synthesized using the Prato reaction of fullerene-C 60 with six different 4-(S-acetylthioalkyl)benzaldehydes. The structures of the synthesized compounds were characterized by FT-IR, 1 H NMR and ESI-MS techniques. The LUMO-HOMO band gaps, derived from DFT B3LYP/6-31G* calculations, for the azomethine ylides corresponding to each 4-(S-acetylthioalkyl)benzaldehyde and fullerene-C 60 were correlated with the efficiency of the Prato reaction. The compounds were deposited onto gold electrodes via self-assembly following an in situ deprotection procedure which transformed the thioacetyl-functionalized compounds into their thiolated derivatives. The redox properties of the C 60 derivatives in solution were characterized using Voltammetry. The LUMO-HOMO band gaps obtained from the electrochemical data were compared with the density functional theory (DFT) values for the optimized structures. The thioacetylfunctionalized C 60 derivatives were employed for the catalytic reduction of halogenated hydrocarbons. Following deprotection, they were also employed for the modification of gold substrates. The solvent dependent barrier properties of the thiolated fullerene films were investigated using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The topography of the C 60 derivative modified electrode was investigated using X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM), which confirmed stable modification of the Au support with a three dimensional (3D) film of worm-like fullerene aggregates.

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This study aimed to develop, characterize, and evaluate antibacterial and cytotoxic properties of novel fullerene derivative composed of C60 fullerenol and standard aminoglycoside antibiotic–gentamicin (C60 fullerenol-gentamicin conjugate). The successful introduction of gentamicin to fullerenol was confirmed by X-ray photoelectron spectroscopy which together with thermogravimetric and spectroscopic analysis revealing the formula of the composition as C60(OH)12(GLYMO)11(Gentamicin)0.8. The dynamic light scattering (DLS) revealed that conjugate possessed ability to form agglomerates in water (size around 115 nm), while Zeta potential measurements demonstrated that such agglomerates possessed neutral character. In vitro biological assays indicated that obtained C60 fullerenol-gentamicin conjugate possessed the same antibacterial activity as standard gentamicin against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli, which proves that combination of fullerenol with gentamicin does not cause the loss of antibacterial activity of antibiotic. Moreover, cytotoxicity assessment demonstrated that obtained fullerenol-gentamicin derivative did not decrease viability of normal human fibroblasts (model eukaryotic cells) compared to control fibroblasts. Thus, taking into account all of the results, it can be stated that this research presents effective method to fabricate C60 fullerenol-gentamicin conjugate and proves that such derivative possesses desired antibacterial properties without unfavorable cytotoxic effects towards eukaryotic cells in vitro. These promising preliminary results indicate that obtained C60 fullerenol-gentamicin conjugate could have biomedical potential. It may be presumed that obtained fullerenol may be used as an effective carrier for antibiotic, and developed fullerenol-gentamicin conjugate may be apply locally (i.e., at the wound site). Moreover, in future we will evaluate possibility of its applications in inter alia tissue engineering, namely as a component of wound dressings and implantable biomaterials.

C60TEMPO10 catalytic system linked to a microspherical gold support through a covalent S-Au bond was developed. The C60TEMPO10@Au composite catalyst had a particle size of 0.5–0.8 μm and was covered with the fullerenes derivative of 2.3 nm diameter bearing ten nitroxyl groups; the organic film showed up to 50 nm thickness. The catalytic composite allowed for the oxidation under mild conditions of various primary and secondary alcohols to the corresponding aldehyde and ketone analogues with efficiencies as high as 79–98%, thus giving values typical for homogeneous catalysis, while retaining at the same time all the advantages of heterogeneous catalysis, e.g., easy separation by filtration from the reaction mixture. The catalytic activity of the resulting system was studied by means of high pressure liquid chromatography. A redox mechanism was proposed for the process. In the catalytic cycle of the oxidation process, the TEMPO moiety was continuously regenerated in situ with an applied primary oxidant, for example, O2/Fe3+ system. The new intermediate composite components and the final catalyst were characterized by various spectroscopic methods and thermogravimetry. Graphical abstractᅟ Electronic supplementary materialThe online version of this article (doi:10.1007/s11051-017-3857-z) contains supplementary material, which is available to authorized users.

A new procedure for the synthesis of S-acetyl-derivatized fullerene is described. The deprotected aromatic S-acetyl-derivatized fullerene was employed for efficient modification of gold electrode and gold nanoparticles. The proposed deposition procedure of fullerene derivative at Au surfaces allows the control of the thickness of the self-assembled fullerene layer. The modified surfaces were characterized by electrochemical methods and X-ray photoelectron spectroscopy (XPS). Functionalized fullerenes largely retain favorable redox electronic properties, behaving as an electron sink and revealing 4 reversible sequential 1e electrode processes at slightly more negative potentials than those observed for unsubstituted C 60 . For the first time, fullerene-capped gold nanoparticles were obtained by a two -step ligand exchange procedure involving substitution of alkanethiol with thiolated fullerene derivative following the synthesis of alkanethiol capped nanoparticles. The ligand exchange procedure was very efficient -the number of fullerene moieties per single gold nanoparticle was found to be as high as 30.