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Sample records for water-soluble fullerene c60

  1. Water-soluble fullerene (c60 inhibits the development of arthritis in the rat model of arthritis

    Directory of Open Access Journals (Sweden)

    Kazuo Yudoh

    2009-10-01

    Full Text Available Kazuo Yudoh1, Rie Karasawa1, Kayo Masuko2, Tomohiro Kato2 1Institute of Medical Science, 2Department of Biochemistry, St. Marianna University School of Medicine, Kawasaki, JapanAbstract: Recently, it has been demonstrated that oxygen free radicals have an important role as a signaling messenger in the development of inflammation and osteoclastogenesis, suggesting the implication of oxygen free radicals in the pathogenesis of arthritis. The aim of this study was to examine the potential of a strong free-radical scavenger, water-soluble fullerene (C60, as a protective agent against synovitis in arthritis, both in vitro and in vivo. In the presence or absence of C60 (0.1, 1.0, 10.0 µM, human synovial fibroblasts, synovial infiltrating lymphocytes or macrophages were incubated with tumor necrosis factor-α (TNF-α (10.0 ng/mL, and the production of proinflammatory cytokines by the individual cells were analyzed. C60 significantly suppressed the TNF-α-induced production of proinflammatory cytokines in synovial fibroblasts, synovial infiltrating lymphocytes and macrophages in vitro. Adjuvant induced arthritic rats were used as an animal model of arthritis. Rats were divided into two subgroups: control and treatment with C60 at 10.0 µM. The left ankle joint was injected intraarticularly with water-soluble C60 (20 µl in the C60-treated group, while, as a control, the left ankle joint in the control rats received phosphate-buffered saline (20 µl, once weekly for eight weeks. Ankle joint tissues were prepared for histological analysis. In adjuvant-induced arthritic rats, intra-articular treatment with C60 in vivo reduced synovitis and alleviated bone resorption and destruction in the joints, while control ankle joints showed progression of synovitis and joint destruction with time. These findings indicate that C60 is a potential therapeutic agent for inhibition of arthritis.Keywords: fullerene, inflammation, arthritis, synovitis, bone resorption

  2. Electronic structure and electrical transport characteristics of C60, 2C60 and 4C60 fullerene molecules

    Institute of Scientific and Technical Information of China (English)

    SHEN Haijun; MU Xiancai

    2007-01-01

    The extended Hückel method and the Green's function method were used to calculate the electronic struc-ture and electrical transport of Au electrode-C60,2C60 or 4C60 fullerene-Au electrode systems.Furthermore,their electronic structure and electrical transport characteristics were com-pared and analyzed.The results show that (I) owing to the contact with the Au electrodes,the C60,2C60 and 4C60 mole-cules change in their electronic structures ignificantly,and their energy gaps between LUMO and HOMO are narrow;(ii) the bonding between C60,2C60 or 4C60 fullerene and Au electrodes is partially covalent and partially electrovalent;and (iii) the conductance of the three fullerenes conforms to the order of C60>2C60>4C60.

  3. Infrared spectroscopy of fullerene C60/anthracene adducts

    CERN Document Server

    Garcia-Hernandez, D A; Manchado, A

    2013-01-01

    Recent Spitzer Space Telescope observations of several astrophysical environments such as Planetary Nebulae, Reflection Nebulae, and R Coronae Borealis stars show the simultaneous presence of mid-infrared features attributed to neutral fullerene molecules (i.e., C60) and polycyclic aromatic hydrocarbons (PAHs). If C60 fullerenes and PAHs coexist in fullerene-rich space environments, then C60 may easily form adducts with a number of different PAH molecules; at least with catacondensed PAHs. Here we present the laboratory infrared spectra (~2-25 um) of C60 fullerene and anthracene Dies-Alder mono- and bis-adducts as produced by sonochemical synthesis. We find that C60/anthracene Diels-Alder adducts display spectral features strikingly similar to those from C60 (and C70) fullerenes and other unidentified infrared emission features. Thus, fullerene-adducts - if formed under astrophysical conditions and stable/abundant enough - may contribute to the infrared emission features observed in fullerene-containing circu...

  4. Water-soluble fullerenes for medical applications

    OpenAIRE

    Rašović, I

    2016-01-01

    Research on fullerenes occupies a unique position in the scientific arena. Synthesis and characterisation of this nanomaterial blur the line between materials science and chemistry; careful tuning of the processing methods gives birth to a whole family of molecules and their functionalised derivatives, whose unusual properties at this nanoscopic scale can be exploited in cutting-edge technological applications. This review focuses on the functionalisation of fullerenes for use in medical appl...

  5. Biological activities of water-soluble fullerene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, S; Mashino, T [Department of Pharmaceutical Sciences, Faculty of Pharmacy, Keio University, 1-5-30 Shiba-koen, Minato-ku, Tokyo 105-8512 (Japan)], E-mail: mashino-td@pha.keio.ac.jp

    2009-04-01

    Three types of water-soluble fullerene derivatives were synthesized and their biological activities were investigated. C{sub 60}-dimalonic acid, an anionic fullerene derivative, showed antioxidant activity such as quenching of superoxide and relief from growth inhibition of E. coli by paraquat. C{sub 60}-bis(7V,7V-dimethylpyrrolidinium iodide), a cationic fullerene derivative, has antibacterial activity and antiproliferative effect on cancer cell lines. The mechanism is suggested to be respiratory chain inhibition by reactive oxygen species produced by the cationic fullerene derivative. Proline-type fullerene derivatives showed strong inhibition activities on HIV-reverse transcriptase. The IC{sub 50} values were remarkably lower than nevirapine, a clinically used anti-HIV drug. Fullerene derivatives have a big potential for a new type of lead compound to be used as medicine.

  6. Active Oxygen Radical Scavenging Ability of Water-Soluble β-Alanine C60 Adducts

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Water-soluble β-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2-and hydroxyl radicalOH were studied by autoxidation ofpyrogallol and chemiluminescence, respectively. It was found that β-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.

  7. Affine Fullerene C60 in a GS-Quasigroup

    Directory of Open Access Journals (Sweden)

    Vladimir Volenec

    2014-01-01

    Full Text Available It will be shown that the affine fullerene C60, which is defined as an affine image of buckminsterfullerene C60, can be obtained only by means of the golden section. The concept of the affine fullerene C60 will be constructed in a general GS-quasigroup using the statements about the relationships between affine regular pentagons and affine regular hexagons. The geometrical interpretation of all discovered relations in a general GS-quasigroup will be given in the GS-quasigroup C(1/2(1+5.

  8. Continuous symmetry of C60 fullerene and its derivatives.

    Science.gov (United States)

    Sheka, E F; Razbirin, B S; Nelson, D K

    2011-04-21

    Conventionally, the I(h) symmetry of fullerene C(60) is accepted, which is supported by numerous calculations. However, this conclusion results from the consideration of the molecule electron system, of its odd electrons in particular, in a closed-shell approximation without taking the electron spin into account. Passing to the open-shell approximation has led to both the energy and the symmetry lowering up to C(i). Seemingly contradicting to a high-symmetry pattern of experimental recording, particularly concerning the molecule electronic spectra, the finding is considered in this Article from the continuous symmetry viewpoint. Exploiting continuous symmetry measure and continuous symmetry level approaches, it was shown that formal C(i) symmetry of the molecule is by 99.99% I(h). A similar continuous symmetry analysis of the fullerene monoderivatives gives a reasonable explanation of a large variety of their optical spectra patterns within the framework of the same C(1) formal symmetry exhibiting a strong stability of the C(60) skeleton. TOC color pictures present chemical portrait of C(60) in terms of atomic chemical susceptibility (Sheka, E. Fullerenes: Nanochemistry, Nanomagnetism, Nanomedicine, Nanophotonics; CRC Press: Taylor and Francis Group, Boca Raton, 2011).

  9. Soil microbial response to photo-degraded C60 fullerenes.

    Science.gov (United States)

    Berry, Timothy D; Clavijo, Andrea P; Zhao, Yingcan; Jafvert, Chad T; Turco, Ronald F; Filley, Timothy R

    2016-04-01

    Recent studies indicate that while unfunctionalized carbon nanomaterials (CNMs) exhibit very low decomposition rates in soils, even minor surface functionalization (e.g., as a result of photochemical weathering) may accelerate microbial decay. We present results from a C60 fullerene-soil incubation study designed to investigate the potential links between photochemical and microbial degradation of photo-irradiated C60. Irradiating aqueous (13)C-labeled C60 with solar-wavelength light resulted in a complex mixture of intermediate products with decreased aromaticity. Although addition of irradiated C60 to soil microcosms had little effect on net soil respiration, excess (13)C in the respired CO2 demonstrates that photo-irradiating C60 enhanced its degradation in soil, with ∼ 0.78% of 60 day photo-irradiated C60 mineralized. Community analysis by DGGE found that soil microbial community structure was altered and depended on the photo-treatment duration. These findings demonstrate how abiotic and biotic transformation processes can couple to influence degradation of CNMs in the natural environment.

  10. Photophysical Properties and Singlet Oxygen Generation Efficiencies of Water-Soluble Fullerene Nanoparticles

    Science.gov (United States)

    Stasheuski, Alexander S; Galievsky, Victor A; Stupak, Alexander P; Dzhagarov, Boris M; Choi, Mi Jin; Chung, Bong Hyun; Jeong, Jin Young

    2014-01-01

    As various fullerene derivatives have been developed, it is necessary to explore their photophysical properties for potential use in photoelectronics and medicine. Here, we address the photophysical properties of newly synthesized water-soluble fullerene-based nanoparticles and polyhydroxylated fullerene as a representative water-soluble fullerene derivative. They show broad emission band arising from a wide-range of excitation energies. It is attributed to the optical transitions from disorder-induced states, which decay in the nanosecond time range. We determine the kinetic properties of the singlet oxygen (1O2) luminescence generated by the fullerene nanoparticles and polyhydroxylated fullerene to consider the potential as photodynamic agents. Triplet state decay of the nanoparticles was longer than 1O2 lifetime in water. Singlet oxygen quantum yield of a series of the fullerene nanoparticles is comparably higher ranging from 0.15 to 0.2 than that of polyhydroxylated fullerene, which is about 0.06. PMID:24893622

  11. Production of anti-fullerene C60 polyclonal antibodies and study of their interaction with a conjugated form of fullerene

    Science.gov (United States)

    Hendrickson, O. D.; Fedyunina, N. S.; Martianov, A. A.; Zherdev, A. V.; Dzantiev, B. B.

    2011-09-01

    The aim of this study was to produce anti-fullerene C60 antibodies for the development of detection systems for fullerene C60 derivatives. To produce anti-fullerene C60 antibodies, conjugates of the fullerene C60 carboxylic derivative with thyroglobulin, soybean trypsin inhibitor, and bovine serum albumin were synthesized by carbodiimide activation and characterized. Immunization of rabbits by the conjugates led to the production of polyclonal anti-fullerene antibodies. The specificity of the immune response to fullerene was investigated. Indirect competitive immunoenzyme assay was developed for the determination of conjugated fullerene with detection limits of 0.04 ng/mL (calculated for coupled C60) and 0.4 ng/mL (accordingly to total fullerene-protein concentration).

  12. Structure and dynamics in self-organized C60 fullerenes.

    Science.gov (United States)

    Patnaik, Archita

    2007-01-01

    This manuscript on 'structure and dynamics in self-organized C60 fullerenes' has three sections dealing with: (A) pristine C60 aggregate structure and geometry in solvents of varying dielectric constant. Here, using positronium (Ps) as a fundamental probe which maps changes in the local electron density of the microenvironment, the onset concentration for stable C60 aggregate formation and its phase behavior is deduced from the specific interactions of the Ps atom with the surrounding. (B) A novel methanofullerene dyad, based on a hydrophobic (acceptor C60 moiety)-hydrophilic (bridge with benzene and ester functionalities)-hydrophobic (donor didodecyloxybenzene) network is chosen for investigation of characteristic self-assembly it undergoes leading to supramolecular aggregates. The pi-electronic amphiphile, necessitating a critical dielectric constant epsilon > or = 30 in binary THF-water mixtures, dictated the formation of bilayer vesicles as precursors for spherical fractal aggregates upon complete dyad extraction into a more polar water phase. (C) While the molecular orientation is dependent on the packing density, the ordering of the molecular arrangement, indispensable for self-assembly depends on the balance between the structures demanded by inter-molecular and molecule-substrate interactions. The molecular orientation in a monolayer affects the orientation in a multilayer, formed on the monolayer, suggesting the possibility of the latter to act as a template for controlling the structure of the three dimensionally grown self-assembled molecular aggregation. A systematic study on the electronic structure and orientation associated with C60 functionalized aminothiol self-assembled monolayers on Au(111) surface is presented using surface sensitive Ultra-Violet Photoelectron Spectroscopy (UPS) and C-K edge Near-Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. The results revealed drastic modifications to d-band structure of Au(111) and the

  13. Neuronal uptake and intracellular superoxide scavenging of a fullerene (C60)-poly(2-oxazoline)s nanoformulation

    KAUST Repository

    Tong, Jing

    2011-05-01

    Fullerene, the third allotrope of carbon, has been referred to as a "radical sponge" because of its powerful radical scavenging activities. However, the hydrophobicity and toxicity associated with fullerene limits its application as a therapeutic antioxidant. In the present study, we sought to overcome these limitations by generating water-soluble nanoformulations of fullerene (C(60)). Fullerene (C(60)) was formulated with poly(N-vinyl pyrrolidine) (PVP) or poly(2-alkyl-2-oxazoline)s (POx) homopolymer and random copolymer to form nano-complexes. These C(60)-polymer complexes were characterized by UV-vis spectroscopy, infrared spectroscopy (IR), dynamic light scattering (DLS), atomic force microscopy (AFM) and transmission electron microscopy (TEM). Cellular uptake and intracellular distribution of the selected formulations in catecholaminergic (CATH.a) neurons were examined by UV-vis spectroscopy, immunofluorescence and immunogold labeling. Electron paramagnetic resonance (EPR) spectroscopy was used to determine the ability of these C(60)-polymer complexes to scavenge superoxide. Their cytotoxicity was evaluated in three different cell lines. C(60)-POx and C(60)-PVP complexes exhibited similar physicochemical properties and antioxidant activities. C(60)-poly(2-ethyl-2-oxazoline) (PEtOx) complex, but not C(60)-PVP complex, were efficiently taken up by CATH.a neurons and attenuated the increase in intra-neuronal superoxide induced by angiotensin II (Ang II) stimulation. These results show that C(60)-POx complexes are non-toxic, neuronal cell permeable, superoxide scavenging antioxidants that might be promising candidates for the treatment of brain-related diseases associated with increased levels of superoxide.

  14. Water-soluble photoluminescent fullerene capped mesoporous silica for pH-responsive drug delivery and bioimaging

    Science.gov (United States)

    Tan, Lei; Wu, Tao; Tang, Zhao-Wen; Xiao, Jian-Yun; Zhuo, Ren-Xi; Shi, Bin; Liu, Chuan-Jun

    2016-08-01

    In this paper, a biocompatible and water-soluble fluorescent fullerene (C60-TEG-COOH) coated mesoporous silica nanoparticle (MSN) was successfully fabricated for pH-sensitive drug release and fluorescent cell imaging. The MSN was first reacted with 3-aminopropyltriethoxysilane to obtain an amino-modified MSN, and then the water-soluble C60 with a carboxyl group was used to cover the surface of the MSN through electrostatic interaction with the amino group in PBS solution (pH = 7.4). The release of doxorubicin hydrochloride (DOX) could be triggered under a mild acidic environment (lysosome, pH = 5.0) due to the protonation of C60-TEG-COO-, which induced the dissociation of the C60-TEG-COOH modified MSN (MSN@C60). Furthermore, the uptake of nanoparticles by cells could be tracked because of the green fluorescent property of the C60-modified MSN. In an in vitro study, the prepared materials showed excellent biocompatibility and the DOX-loaded nanocarrier exhibited efficient anticancer ability. This work offered a simple method for designing a simultaneous pH-responsive drug delivery and bioimaging system.

  15. Synthesis of water-soluble cystine C60 derivative with catalyst and its active oxygen radical scavenging ability

    Institute of Scientific and Technical Information of China (English)

    Wen Chao Guan; Xiang Ying Tang; Li Zhen Huang; Hong Xu

    2007-01-01

    A novel water-soluble cystine C60 derivative was synthesized in the presence of the catalyst, tetrabutylammonium hydroxide (TBAH). The product was characterized by FT-IR, UV, 1H NMR, 13C NMR, MS and elemental analysis. Furthermore, the that cystine C60 derivative showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50%inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.167 and 0.008 mg/mL, respectively.

  16. Biodistribution of fullerene derivative C60(OH)x(O)y

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The biological behavior of fullerene derivatives shows their considerable potential application in medicine field. To understand the biodistribution of C60 derivatives as drugs or drug carriers, a simple water-soluble derivative C60(OH)x(O)y was labeled with 99mTc. A y-counter and a sin gle photo emission computed tomography (SPECT) were used to assess the biodistribution and metabolism of the la beled compound in mice and rabbits, respectively. The re sults showed that the compound could be absorbed rapidly by tissues, especially by coronal bone, breastbone, backbone,extremity honeycomb, liver and spleen. The clearance was slow from all tissues except for brain. The compound might be excreted through urine and enteron. The biodistribution shows some difference from that of Yamago et al. In this note,we discuss the possible reason leading to the difference. Fur ther study is needed to find out to what extent the C60 itself determines the biodistribution of derivatives.

  17. Synthesis of water-soluble C60 derivatives and their scavenging free radical activity

    Institute of Scientific and Technical Information of China (English)

    尹桂; 徐正

    2002-01-01

    Four piperazine-appended [60] fullerenes(1a-1d) were synthesized and characterized. Their activities of scavenging radical were studied via UV-Vis and EPR. The results indicate that light irradiation is of advantage to increase the activity of scavenging radical.

  18. Variation of Excited-State Dynamics in Trifluoromethyl Functionalized C60 Fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jaehong; Ramirez, Jessica J.; Clikeman, Tyler T.; Larson, Bryon W.; Boltalina, Olga V.; Strauss, Steven H.; Rumbles, Garry

    2016-09-07

    We report on electronically excited-state dynamics of three different trifluoromethyl C60 fullerenes (TMFs, C60(CF3)n: C60/4-1, C60/6-2, and C60/10-1, featuring four, six, and ten trifluoromethyl groups, respectively) using steady-state and time-resolved optical spectroscopy as well as ultrafast pump/probe transient absorption spectroscopy. C60/4-1 and C60/6-2 dissolved in toluene solvent show near-unity S1--T1 intersystem crossing quantum yield (..phi..ISC), ca. 1 ns S1-state lifetimes, and microsecond-timescale T1-state lifetimes, which are typical of the fullerene class. On the other hand, C60/10-1 exhibits a dominant sub-nanosecond nonradiative S1--S0 relaxation mechanism and negligible ..phi..ISC, therefore decreasing the average excited-state lifetime (..tau..avg) by about 5 orders of magnitude compared to that of C60/4-1 and C60/6-2 (..tau..avg approx. 17 us and 54 us for C60/4-1 and C60/6-2, respectively, whereas ..tau..avg approx. 100 ps for C60/10-1). These excited-state characteristics of C60/4-1 and C60/6-2 are preserved in polymer matrix, suggesting that fullerene/polymer interactions do not modulate intrinsic photophysics of trifluoromethyl-substituted fullerenes. The contrasting excited- state study results of C60/4-1 and C60/6-2 to that of C60/10-1 infer that intrinsic optical properties and excited-state dynamics can be affected by the substitution on the fullerene.

  19. Adlayers of C60-C60 and C60-C70 fullerene dimers formed on au(111) in benzene solutions studied by STM and LEED.

    Science.gov (United States)

    Matsumoto, Masashi; Inukai, Junji; Tsutsumi, Eishi; Yoshimoto, Soichiro; Itaya, Kingo; Ito, Osamu; Fujiwara, Koichi; Murata, Michihisa; Murata, Yasujiro; Komatsu, Koichi

    2004-02-17

    Scanning tunneling microscopy (STM) and low-energy electron diffraction were used to reveal the structures of ordered adlayers of [2+2]-type C60-C60 fullerene dimer (C120) and C60-C70 cross-dimer (C130) formed on Au(111) by immersingit in abenzene solution containing C120 or C130 molecules. High-resolution STM images clearly showed the packing arrangements and the electronic structures of C120 and C130 on the Au(111) surface in ultrahigh vacuum. The (2 square root3 x 4square root3)R30 degrees, (2square root3 x 5square root3)R30 degrees, and (7 x 7) structures were found for the C120 adlayer on the Au(111) surface, whereas C130 molecules were closely packed on the surface. Each C60 or C70 monomer cage was discerned in the STM image of a C130 molecule.

  20. Fullerene Molecule Strain in $RbC_{60}$

    CERN Document Server

    Aksenov, V L; Forró, L; Khasanov, S S; Chernyshev, V V; Shakhmatov, V S

    2000-01-01

    Strain displacements of carbon atoms in a C$_60$ molecule in the $Pnnm$ phase of the RbC$_60$ fulleride are first determined by X-ray diffraction. The measurements show that the polymeric bond length between carbon atoms of two nearest molecules C$_60$ is equal to 1.69(1) $\\AA$, the rotation angle of the molecule about the polymeric direction is 47.0(3)$^0$.

  1. USING OF C60 FULLERENE COMPLEXES WITH ANTITUMOR DRUGS IN CHEMOTHERAPY

    Directory of Open Access Journals (Sweden)

    S. V. Prylutska

    2014-06-01

    Full Text Available The literature data and own research results concerning antitumor effect in vitro and in vivo of C60 fullerene and its derivatives, cytostatics, and conjugated systems on their basis, which enable the practical application of C60 in combined chemotherapy for treatment efficacy improving of malignant tumors are generalized. The mechanism of antitumor action of C60 fullerene in combined treatment with cytostatics is based on antioxidant properties of its molecule, thereby reducing toxic side effects of traditional drugs in a body and ability to their transport purposefully into the target cells. The unique structure of C60 enables to modify its surface with chemotherapeutic drugs. Under combined action of the "fullerene C60-chemotherapy drug" conjugate the anti-tumor effects enhancement is observed both in vitro and in vivo, namely quantity reduction of viable tumor cells, tumor reduction etc. Furthermore, protective effects of fullerene C60 and derivatives relatively toxic effects of chemotherapeutic agents in a body were observed. Conjugate auxesis empowers it to be kept longer in a cell and prolong the duration of drug action. Ability of fullerene C60 to selective accumulation provides its using for target drug delivery.

  2. Fullerene molecule strain in RbC 60

    Science.gov (United States)

    Aksenov, V. L.; Ossipyan, Yu. À.; Forro, L.; Khasanov, S.; Chernyshev, V. V.; Shakhmatov, V. S.

    2000-04-01

    Strain displacements of carbon atoms in a Ñ 60 molecule in the Pnnm phase of the RbC 60 fulleride are first determined by X-ray diffraction. The measurements show that the polymeric bond length between carbon atoms of two nearest molecules C 60 is equal to 1.69(1) Å, the rotation angle of the molecule about the polymeric direction is 47.0(3)°.

  3. Anion-Dependent Aggregate Formation and Charge Behavior of Colloidal Fullerenes (n-C60)

    Science.gov (United States)

    The fate and transport of colloidal fullerenes (n-C60) in the environment is likely to be guided by electrokinetic and aggregation behavior. In natural water bodies inorganic ions exert significant effects in determining the size and charge of n-C60 nanoparticles. Although the ef...

  4. Synthesis of a Crushed Fullerene C60H24 through Sixfold Palladium-Catalyzed Arylation.

    Science.gov (United States)

    Dorel, Ruth; de Mendoza, Paula; Calleja, Pilar; Pascual, Sergio; González-Cantalapiedra, Esther; Cabello, Noemí; Echavarren, Antonio M

    2016-07-01

    The synthesis of a new C3v -symmetric crushed fullerene C60H24 (5) has been accomplished in three steps from truxene through sixfold palladium-catalyzed intramolecular arylation of a syn-trialkylated truxene precursor. Laser irradiation of 5 induces cyclodehydrogenation processes that result in the formation of C60, as detected by LDI-MS.

  5. Synthesis of a Crushed Fullerene C60H24 through Sixfold Palladium‐Catalyzed Arylation

    Science.gov (United States)

    Dorel, Ruth; de Mendoza, Paula; Calleja, Pilar; Pascual, Sergio; González‐Cantalapiedra, Esther; Cabello, Noemí

    2016-01-01

    The synthesis of a new C 3v‐symmetric crushed fullerene C60H24 (5) has been accomplished in three steps from truxene through sixfold palladium‐catalyzed intramolecular arylation of a syn‐trialkylated truxene precursor. Laser irradiation of 5 induces cyclodehydrogenation processes that result in the formation of C60, as detected by LDI‐MS. PMID:27774038

  6. Synthesis and properties of novel water-soluble fullerene-glycine derivatives as new materials for cancer therapy.

    Science.gov (United States)

    Jiang, Guichang; Yin, Fen; Duan, Jihua; Li, Guangtao

    2015-01-01

    Novel water-soluble fullerene-glycine derivatives were synthesized by means of simple organic chemistry. They are completely soluble in water, yielding a clear brown solution. The products were characterized by fourier transform infrared (FTIR), ultraviolet-visible spectroscopy (UV-Vis), (1)H NMR, (13)C NMR, thermogravimetric analyses (TGA), and scanning electron microscopy (SEM). The assembly behavior of water-soluble fullerene-glycine derivatives was investigated by SEM. The results show that the fullerene-glycine derivatives create morphology that is sphere-like. The cytotoxicity to cancer cell lines of the fullerene-glycine derivatives was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and flow cytometry. The results show that fullerene-glycine derivatives exhibit mortality and apoptosis of the cells which increased with the increase of fullerene-glycine derivative concentration. The cytotoxicity mechanism of fullerene-glycine derivatives was investigated for the first time. Novel water-soluble fullerene-glycine derivatives were synthesized by means of simple organic chemistry. The products were characterized by FTIR, UV-Vis, (1)H NMR, (13)C NMR, TGA, and SEM. The bioactivities of fullerene-glycine derivative materials have been tested, and the results show that compared with the fullerene complex, the fullerene-glycine derivative materials exhibit mortality and apoptosis of the cells which increased with the increase of fullerene-glycine derivative concentration. SEM images showed the macrostructure of fullerene-glycine derivative materials was spheres.

  7. Biological safety of LipoFullerene composed of squalane and fullerene-C60 upon mutagenesis, photocytotoxicity, and permeability into the human skin tissue.

    Science.gov (United States)

    Kato, Shinya; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2009-06-01

    Fullerene-C60 (C60) is mainly applied in the aqueous phase by wrapping with water-soluble polymer or by water-solublizing chemical-modification, whereas C60 dissolved in oil is scarcely applied; still less explicable is its toxicity.We dissolved C60 in squalane at near-saturated or higher concentrations (220-500 ppm), named LipoFullerene (LF-SQ),and examined its biological safety. LF-SQ was administered at doses of 0.49-1000 microg/ml to fibroblast cells Balb/3T3, and showed that cell viability was almost equal to that of the control regardless of the UVA- or sham-irradiation, indicating no phototoxicity. Reverse mutation by LF-SQ was examined on four histidine-demanding strains of Salmonella typhimurium and a tryptophan-demanding strain of Escherichia coli. As for the dosages of LF-SQ (313-5000 microg/plate), the dose-dependency of the number of reverse mutation colonies of each strain did not show a marked difference when compared with the negative control, regardless of the metabolic activation, in contrast to twice or more differences for five positive controls(sodium azide, N-ethyl-N'-nitro-N-nitrosoguanidine, 2-nitrofluorene, 9-aminoacridine, and 2-aminoanthracene). In human skin biopsy built in a diffusion chamber, C60 permeated into the epidermis at 33.6 nmol/g tissue (24.2 ppm), on administration with LF-SQ containing 223 ppm of C60, but not detected in the dermis even after 24 hrs, as analysed by HPLC. It is presumed that LF-SQ can permeate into the epidermis via the corneum but can not penetrate the basement membrane,and so can not reach into the dermis, suggesting no necessity for considering a toxicity of C60 due to systemic circulation via dermal veins. Thus, C60 dissolved in squalane may not give any significant biological toxic effects such as photocytotoxicity,bacterial reverse mutagenicity, and permeability into the human skin.

  8. C60-Fullerenes: detection of intracellular photoluminescence and lack of cytotoxic effects

    Directory of Open Access Journals (Sweden)

    Carroll David L

    2006-12-01

    Full Text Available Abstract We have developed a new method of application of C60 to cultured cells that does not require water-solubilization techniques. Normal and malignant cells take-up C60 and the inherent photoluminescence of C60 is detected within multiple cell lines. Treatment of cells with up to 200 μg/ml (200 ppm of C60 does not alter morphology, cytoskeletal organization, cell cycle dynamics nor does it inhibit cell proliferation. Our work shows that pristine C60 is non-toxic to the cells, and suggests that fullerene-based nanocarriers may be used for biomedical applications.

  9. Preparation and tribology properties of water-soluble fullerene derivative nanoball

    Directory of Open Access Journals (Sweden)

    Guichang Jiang

    2017-02-01

    Full Text Available Water-soluble fullerene derivatives were synthesized via radical polymerization. They are completely soluble in water, yielding a clear brown solution. The products were characterized by FTIR, UV–Vis, 1H-NMR, 13CNMR, GPC, TGA, and SEM. Four-ball tests show that the addition of a certain concentration of the fullerene derivatives to base stock (2 wt.% triethanolamine aqueous solution can effectively increase both the load-carrying capacity (PB value, and the resistance to wear. SEM observations confirm the additive results in a reduced diameter of the wear scar and decreased wear.

  10. New Ruthenium Complexes of Fullerene C60&C70

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The new complexes [Ru(NO)(PPh3)]2(η2-Cm)(m=60 1 or 70 2) have been prepared by heating a solution of C60(or C70) with [Ru(NO)2(PPh3)2] in toluene. They have been characterized by elemental analysis, IR, UV/VIS, XPS, 13C and 31P NMR spectroscopy. The photovaltaic effect for the new compounds has been studied.

  11. Interceptor effect of C60 fullerene on the in vitro action of aromatic drug molecules.

    Science.gov (United States)

    Skamrova, Galyna B; Laponogov, Ivan; Buchelnikov, Anatoly S; Shckorbatov, Yuriy G; Prylutska, Svitlana V; Ritter, Uwe; Prylutskyy, Yuriy I; Evstigneev, Maxim P

    2014-07-01

    C60 fullerenes are spherical molecules composed purely of carbon atoms. They inspire a particularly strong scientific interest because of their specific physico-chemical properties and potential medical and nanotechnological applications. In this work we are focusing on studying the influence of the pristine C60 fullerene on biological activity of some aromatic drug molecules in human buccal epithelial cells. Assessment of the heterochromatin structure in the cell nucleus as well as the barrier function of the cell membrane was performed. The methods of cell microelectrophoresis and atomic force microscopy were also applied. A concentration-dependent restoration of the functional activity of the cellular nucleus after exposure to DNA-binding drugs (doxorubicin, proflavine and ethidium bromide) has been observed in human buccal epithelial cells upon addition of C60 fullerene at a concentration of ~10(-5 )M. The results were shown to follow the framework of interceptor/protector action theory, assuming that non-covalent complexation between C60 fullerene and the drugs (i.e., hetero-association) is the major process responsible for the observed biological effects. An independent confirmation of this hypothesis was obtained via investigation of the cellular response of buccal epithelium to the coadministration of the aromatic drugs and caffeine, and it is based on the well-established role of hetero-association in drug-caffeine systems. The results indicate that C60 fullerene may reverse the effects caused by the aromatic drugs, thereby pointing out the potential possibility of the use of aromatic drugs in combination with C60 fullerene for regulation of their medico-biological action.

  12. Detection of fullerenes (C60 and C70) in commercial cosmetics

    Science.gov (United States)

    Benn, Troy M.; Westerhoff, Paul; Herckes, Pierre

    2013-01-01

    Detection methods are necessary to quantify fullerenes in commercial applications to provide potential exposure levels for future risk assessments of fullerene technologies. The fullerene concentrations of five cosmetic products were evaluated using liquid chromatography with mass spectrometry to separate and specifically detect C60 and C70 from interfering cosmetic substances (e.g., castor oil). A cosmetic formulation was characterized with transmission electron microscopy, which confirmed that polyvinylpyrrolidone encapsulated C60. Liquid-liquid extraction of fullerenes from control samples approached 100% while solid-phase and sonication in toluene extractions yielded recoveries of 27–42%. C60 was detected in four commercial cosmetics ranging from 0.04 to 1.1 μg/g, and C70 was qualitatively detected in two samples. A single-use quantity of cosmetic (0.5 g) may contain up to 0.6 μg of C60, demonstrating a pathway for human exposure. Steady-state modeling of fullerene adsorption to biosolids is used to discuss potential environmental releases from wastewater treatment systems. PMID:21300421

  13. Fullerene C60 Penetration into Leukemic Cells and Its Photoinduced Cytotoxic Effects

    Science.gov (United States)

    Franskevych, D.; Palyvoda, K.; Petukhov, D.; Prylutska, S.; Grynyuk, I.; Schuetze, C.; Drobot, L.; Matyshevska, O.; Ritter, U.

    2017-01-01

    Fullerene C60 as a representative of carbon nanocompounds is suggested to be promising agent for application in photodynamic therapy due to its unique physicochemical properties. The goal of this study was to estimate the accumulation of fullerene C60 in leukemic cells and to investigate its phototoxic effect on parental and resistant to cisplatin leukemic cells. Stable homogeneous water colloid solution of pristine C60 with average 50-nm diameter of nanoparticles was used in experiments. Fluorescent labeled C60 was synthesized by covalent conjugation of C60 with rhodamine B isothiocyanate. The results of confocal microscopy showed that leukemic Jurkat cells could effectively uptake fullerene C60 from the medium. Light-emitting diode lamp (100 mW cm-2, λ = 420-700 nm) was used for excitation of accumulated C60. A time-dependent decrease of viability was detected when leukemic Jurkat cells were exposed to combined treatment with C60 and visible light. The cytotoxic effect of photoexcited C60 was comparable with that induced by H2O2, as both agents caused 50% decrease of cell viability at 24 h at concentrations about 50 μM. Using immunoblot analysis, protein phosphotyrosine levels in cells were estimated. Combined action of C60 and visible light was followed by decrease of cellular proteins phosphorylation on tyrosine residues though less intensive as compared with that induced by H2O2 or protein tyrosine kinase inhibitor staurosporine. All tested agents reduced phosphorylation of 55, 70, and 90 kDa proteins while total suppression of 26 kDa protein phosphorylation was specific only for photoexcited C60.

  14. C60 fullerenes from combustion of common fuels

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Andrea J., E-mail: ajtiwari@vt.edu [Department of Civil & Environmental Engineering, Virginia Tech, 200 Patton Hall, 750 Drillfield Drive, Blacksburg, VA 24061 (United States); Ashraf-Khorassani, Mehdi, E-mail: mashraf@vt.edu [Department of Chemistry, Virginia Tech, 480 Davidson Hall, 900 West Campus Drive, Virginia Tech, Blacksburg, VA 24061 (United States); Marr, Linsey C., E-mail: lmarr@vt.edu [Department of Civil & Environmental Engineering, Virginia Tech, 200 Patton Hall, 750 Drillfield Drive, Blacksburg, VA 24061 (United States)

    2016-03-15

    Releases of C{sub 60} fullerenes to the environment will increase with the growth of nanotechnology. Assessing the potential risks of manufactured C{sub 60} requires an understanding of how its prevalence in the environment compares to that of natural and incidental C{sub 60}. This work describes the characterization of incidental C{sub 60} present in aerosols generated by combustion of five common fuels: coal, firewood, diesel, gasoline, and propane. C{sub 60} was found in exhaust generated by all five fuels; the highest concentrations in terms of mass of C{sub 60} per mass of particulate matter were associated with diesel and coal. Individual aerosols from these combustion processes were examined by transmission electron microscopy. No relationship was found between C{sub 60} content and either the separation of graphitic layers (lamellae) within the particles, nor the curvature of those lamellae. Estimated global emissions of incidental C{sub 60} to the atmosphere from coal and diesel combustion range from 1.6 to 6.3 t yr{sup −1}, depending upon combustion conditions. These emissions may be similar in magnitude to the total amount of manufactured C{sub 60} produced on an annual basis. Consequent loading of incidental C{sub 60} to the environment may be several orders of magnitude higher than has previously been modeled for manufactured C{sub 60}. - Highlights: • Exhaust of common fuels (coal, diesel, etc.) analyzed via chromatography for C{sub 60.} • All five fuels tested produced C{sub 60} in aerosols in mass fractions up to several ppm. • Emissions of incidental C{sub 60} may be comparable to the total amount manufactured.

  15. Self-Cleaning Photocatalytic Polyurethane Coatings Containing Modified C60 Fullerene Additives

    OpenAIRE

    Jeffrey G. Lundin; Spencer L. Giles; Robert F. Cozzens; Wynne, James H.

    2014-01-01

    Surfaces are often coated with paint for improved aesthetics and protection; however, additional functionalities that impart continuous self-decontaminating and self-cleaning properties would be extremely advantageous. In this report, photochemical additives based on C60 fullerene were incorporated into polyurethane coatings to investigate their coating compatibility and ability to impart chemical decontaminating capability to the coating surface. C60 exhibits unique photophysical properties,...

  16. Non-detection of C60 fullerene at two mass extinction horizons

    Science.gov (United States)

    Carrasquillo, Anthony J.; Cao, Changqun; Erwin, Douglas H.; Summons, Roger E.

    2016-03-01

    Fullerene (C60) have been reported in a number of geologic samples and, in some cases, attributed to carbonaceous materials delivered during bolide impact events. The extraction and detection of C60 poses significant analytical challenges, and some studies have been called into question due to the possibility of C60 forming in situ. Here, we extracted samples taken from the Permian-Triassic boundary section in Meishan, South China and the Cretaceous-Paleogene boundary exposed at Stevns Klint, Denmark, and analyzed the residues using a fast and reliable method for quantifying C60. Extraction of both whole rock and completely demineralized samples were completed under conditions that previously yielded C60 as well as using an optimized approach based on recent literature reports. These extracts were analyzed using mass spectrometry with the soft-ionization techniques, atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), which have not been shown to form fullerenes in-situ. In no case were we able to detect C60, nor could we corroborate previous reports of its occurrence in these sediments, thereby challenging the utility of fullerene as a proxy for bolide impacts or mass extinction events.

  17. Potential Suppressive Effects of Two C60 Fullerene Derivatives on Acquired Immunity

    Science.gov (United States)

    Hirai, Toshiro; Yoshioka, Yasuo; Udaka, Asako; Uemura, Eiichiro; Ohe, Tomoyuki; Aoshima, Hisae; Gao, Jian-Qing; Kokubo, Ken; Oshima, Takumi; Nagano, Kazuya; Higashisaka, Kazuma; Mashino, Tadahiko; Tsutsumi, Yasuo

    2016-10-01

    The therapeutic effects of fullerene derivatives on many models of inflammatory disease have been demonstrated. The anti-inflammatory mechanisms of these nanoparticles remain to be elucidated, though their beneficial roles in allergy and autoimmune diseases suggest their suppressive potential in acquired immunity. Here, we evaluated the effects of C60 pyrrolidine tris-acid (C60-P) and polyhydroxylated fullerene (C60(OH)36) on the acquired immune response in vitro and in vivo. In vitro, both C60 derivatives had dose-dependent suppressive effects on T cell receptor-mediated activation of T cells and antibody production by B cells under anti-CD40/IL-4 stimulation, similar to the actions of the antioxidant N-acetylcysteine. In addition, C60-P suppressed ovalbumin-specific antibody production and ovalbumin-specific T cell responses in vivo, although T cell-independent antibodies responses were not affected by C60-P. Together, our data suggest that fullerene derivatives can suppress acquired immune responses that require T cells.

  18. Development and Characterization of Biocompatible Fullerene [C60]/Amphiphilic Block Copolymer Nanocomposite

    Directory of Open Access Journals (Sweden)

    Alok Chaurasia

    2015-01-01

    Full Text Available We report a supramolecular process for the synthesis of well-defined fullerene (C60/polymer colloid nanocomposites in an aqueous solution via complex formation. A biocompatible triblock poly(4-vinylpyridine-b-polyethylene-b-poly(4-vinylpyridine, P4VP8-b-PEO105-b-P4VP8, was synthesized by atom transfer radical polymerization. The block copolymer formed complexes with C60 in toluene and resulted in fullerene assembly in cluster form. Nanocomposite dispersion in an aqueous solution could be obtained using an aged solution of the polymer/C60/toluene solution by a solvent evaporation technique. The UV-Vis and FTIR spectroscopy confirmed the complex formation of fullerene with the polymer which plays a significant role in controlling the PDI and size of polymer/C60 micelles in the toluene solution. The particle size and morphology of P4VP8-b-PEO105-b-P4VP8 and P4VP8-b-PEO105-b-P4VP8/C60 mixture were studied by dynamic light scattering (DLS and transmission electron microscopy (TEM. In a cytotoxicity test, both pure polymer and the resulting polymer/C60 composite in water showed more than 90% cell viability at 1 mg/mL concentration.

  19. Conformational, IR spectroscopic and electronic properties of conium alkaloids and their adducts with C60 fullerene

    Science.gov (United States)

    Zabolotnyi, M. A.; Prylutskyy, Yu I.; Poluyan, N. A.; Evstigneev, M. P.; Dovbeshko, G. I.

    2016-08-01

    Conformational, IR spectroscopic and electronic properties of the components of Conium alkaloids (Conium maculatum) in aqueous environment were determined by model calculations and experiment. With the help of FT-IR spectroscopy the possibility of formation of an adduct between γ-coniceine alkaloid and C60 fullerene was demonstrated, which is important for further application of conium analogues in biomedical purposes.

  20. Ab-initio modeling of an anion $C_{60}^-$ pseudopotential for fullerene-based compounds

    CERN Document Server

    Vrubel, I I; Ivanov, V K

    2015-01-01

    A pseudopotential of $C_{60}^-$ has been constructed from ab-initio quantum-mechanical calculations. Since the obtained pseudopotential can be easily fitted by rather simple analytical approximation it can be effectively used both in classical and quantum molecular dynamics of fullerene-based compounds.

  1. Recent Advances in Electrochemical Biosensors Based on Fullerene-C60 Nano-Structured Platforms

    Directory of Open Access Journals (Sweden)

    Sanaz Pilehvar

    2015-11-01

    Full Text Available Nanotechnology is becoming increasingly important in the field of (biosensors. The performance and sensitivity of biosensors is greatly improved with the integration of nanomaterials into their construction. Since its first discovery, fullerene-C60 has been the object of extensive research. Its unique and favorable characteristics of easy chemical modification, conductivity, and electrochemical properties has led to its tremendous use in (biosensor applications. This paper provides a concise review of advances in fullerene-C60 research and its use as a nanomaterial for the development of biosensors. We examine the research work reported in the literature on the synthesis, functionalization, approaches to nanostructuring electrodes with fullerene, and outline some of the exciting applications in the field of (biosensing.

  2. Recent Advances in Electrochemical Biosensors Based on Fullerene-C60 Nano-Structured Platforms.

    Science.gov (United States)

    Pilehvar, Sanaz; De Wael, Karolien

    2015-11-23

    Nanotechnology is becoming increasingly important in the field of (bio)sensors. The performance and sensitivity of biosensors is greatly improved with the integration of nanomaterials into their construction. Since its first discovery, fullerene-C60 has been the object of extensive research. Its unique and favorable characteristics of easy chemical modification, conductivity, and electrochemical properties has led to its tremendous use in (bio)sensor applications. This paper provides a concise review of advances in fullerene-C60 research and its use as a nanomaterial for the development of biosensors. We examine the research work reported in the literature on the synthesis, functionalization, approaches to nanostructuring electrodes with fullerene, and outline some of the exciting applications in the field of (bio)sensing.

  3. Toxic effect of C60 fullerene-doxorubicin complex towards tumor and normal cells in vitro

    Directory of Open Access Journals (Sweden)

    Prylutska S. V.

    2014-09-01

    Full Text Available Creation of new nanostructures possessing high antitumor activity is an important problem of modern biotechnology. Aim. To evaluate cytotoxicity of created complex of pristine C60 fullerene with the anthracycline antibiotic doxorubicin (Dox, as well as of free C60 fullerene and Dox, towards different cell types – tumor, normal immunocompetent and hepatocytes. Methods. Measurement of size distribution for particles in C60 + Dox mixture was performed by a dynamic light scattering (DLS technique. Toxic effect of C60 + Dox complex in vitro towards tumor and normal cells was studied using the MTT assay. Results. DLS experiment demonstrated that the main fraction of the particles in C60 + Dox mixture had a diameter in the range of about 132 nm. The toxic effect of C60 + Dox complex towards normal (lymphocytes, macrophages, hepatocytes and tumor (Ehrlich ascites carcinoma, leukemia L1210, Lewis lung carcinoma cells was decreased by ~10–16 % and ~7–9 %, accordingly, compared with the same effect of free Dox. Conclusions. The created C60 + Dox composite may be considered as a new pharmacological agent that kills effectively tumor cells in vitro and simultaneously prevents a toxic effect of the free form of Dox on normal cells.

  4. Toxicity of Aqueous Fullerene nC60 to Activated Sludge: Nitrification Inhibition and Microtox Test

    Directory of Open Access Journals (Sweden)

    Yongkui Yang

    2012-01-01

    Full Text Available The increasing production and use of fullerene nanomaterials raised their exposure potential to the activated sludge during biological wastewater treatment process. In this study, the toxicity of aqueous nanoscaled C60 (nC60 to activated sludge was investigated using nitrification inhibition and Microtox test. The test solutions of nC60 were prepared using two methods: long stirring (Stir/nC60 and toluene exchange (Tol/nC60. The nC60 aggregation in test medium was also evaluated for toxicity assessment. The results showed that the nC60 aggregation behaved differently in two test mediums during the incubation periods. The nC60 toxicity was greatly influenced by the preparation method. Stir/nC60 presented no significant toxicity to both the nitrification sludge and bioluminescent bacteria at the maximum concentration studied. In contrast, the EC20 of Tol/nC60 was obtained to be 4.89 mg/L (3 h for the nitrification inhibition and 3.44 mg/L (30 min for Microtox test, respectively.

  5. Heterostructures based on graphene and MoS2 layers decorated by C60 fullerenes

    Science.gov (United States)

    Chernozatonskii, Leonid A.; Kvashnin, Alexander G.; Sorokin, Pavel B.

    2016-09-01

    Here we present a comprehensive investigation of various novel composite structures based on graphene (G) and molybdenum disulphide (MoS2) monolayers decorated by C60 fullerenes, which can be successfully applied in photovoltaics as a solar cell unit. Theoretical studies of the atomic structure, stability and electronic properties of the proposed G/C60, MoS2/C60 and G/MoS2/C60/G nanostructures were carried out. We show that making the G/MoS2/C60/G heterostructure from the 2D films considered here will lead to the appearance of particular properties suitable for application in photovoltaics due to the broad energetic region of high electronic density of states.

  6. Study of the interaction of C60 fullerene with human serum albumin in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Li, Song [Vanderbilt University; Zhao, Xiongce [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health; Mo, Yiming [ORNL; Cummings, Peter T [ORNL; Heller, William T [ORNL

    2013-01-01

    Concern about the toxicity of engineered nanoparticles, such as the prototypical nanomaterial C60 fullerene, continues to grow. While evidence continues to mount that C60 and its derivatives may pose health hazards, the specific molecular interactions of these particles with biological macromolecules require further investigation. To better understand the interaction of C60 with proteins, the protein human serum albumin (HSA) was studied in solution with C60 at C60:HSA molar ratios ranging from 1:2 to 4:1. HSA is the major protein component of blood plasma and plays a role in a variety of functions, such as the maintenance of blood pH and pressure. The C60-HSA interaction was probed by a combination of circular dichroism (CD) spectroscopy, small-angle neutron scattering (SANS) and atomistic molecular dynamics (MD) simulations to understand C60-driven changes in the structure of HSA in solution. The CD spectroscopy demonstrates that the secondary structure of the protein decreases in -helical content in response to the presence of C60. Similarly, C60 produces subtle changes in the solution conformation of HSA, as evidenced by the SANS data and MD. The data do not indicate that C60 is causing a change in the oligomerization state of the protein. Taken together results demonstrate that C60 interacts with HSA, but it does not strongly perturb the structure of the protein by unfolding it or inducing aggregation, suggesting a mechanism for transporting C60 throughout the body to accumulate in various tissues.

  7. Growth of Fullerene Fragments Using the Diels-Alder Cycloaddition Reaction: First Step towards a C60 Synthesis by Dimerization

    Directory of Open Access Journals (Sweden)

    Julio A. Alonso

    2013-02-01

    Full Text Available Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to dimerize fullerene fragments, as a way to obtain C60. The dienophile character of the fullerene fragments is dominant, and the reaction of butadiene with pentacyclopentacorannulene is favored.

  8. Self-Cleaning Photocatalytic Polyurethane Coatings Containing Modified C60 Fullerene Additives

    Directory of Open Access Journals (Sweden)

    Jeffrey G. Lundin

    2014-08-01

    Full Text Available Surfaces are often coated with paint for improved aesthetics and protection; however, additional functionalities that impart continuous self-decontaminating and self-cleaning properties would be extremely advantageous. In this report, photochemical additives based on C60 fullerene were incorporated into polyurethane coatings to investigate their coating compatibility and ability to impart chemical decontaminating capability to the coating surface. C60 exhibits unique photophysical properties, including the capability to generate singlet oxygen upon exposure to visible light; however, C60 fullerene exhibits poor solubility in solvents commonly employed in coating applications. A modified C60 containing a hydrophilic moiety was synthesized to improve polyurethane compatibility and facilitate segregation to the polymer–air interface. Bulk properties of the polyurethane films were analyzed to investigate additive–coating compatibility. Coatings containing photoactive additives were subjected to self-decontamination challenges against representative chemical contaminants and the effects of additive loading concentration, light exposure, and time on chemical decontamination are reported. Covalent attachment of an ethylene glycol tail to C60 improved its solubility and dispersion in a hydrophobic polyurethane matrix. Decomposition products resulting from oxidation were observed in addition to a direct correlation between additive loading concentration and decomposition of surface-residing contaminants. The degradation pathways deduced from contaminant challenge byproduct analyses are detailed.

  9. Transport and retention of fullerene (C60) nanoparticles in natural soils

    Science.gov (United States)

    Wang, Y.; Li, Y.; Abriola, L. M.; Pennell, K. D.

    2008-12-01

    Although several column studies have investigated the transport and deposition of fullerene (C60) nanoparticles in ideal porous media, such as washed quartz sands and glass beads, far less attention has been directed toward natural soils. To address this issue, a series of column experiments was performed to quantify the transport and retention of C60 nanoparticles in a borosilicate glass column (10 cm length x 2.5 cm dia.) packed with either Appling soil or Webster soil. Introduction of a C60 suspension containing 1 mM calcium chloride as background electrolyte for up to 65 pore volumes resulted in 100 percent retention of injected mass. Retained C60 nanoparticles were concentrated within 6 cm of the column from inlet, with solid phase concentrations approaching 130 μg/g. The presence of Suwannee River humic acid (20 mg/L) in the C60 suspension slightly enhanced mobility of nC60, although effluent breakthrough was not observed. However, when mixed with 1,000 mg/L polyethoxylate (20) sorbitan monooleate (Tween 80), C60 nanoparticles were readily transported through Appling soil, with less than 40 percent of injected mass retained. Retentions profiles of nC60 exhibited gradual ascent and descent, but not symmetrically, with distance from inlet. A mathematic transport model incorporating classical filtration theory, non-linear sorption process, and straining was utilized to capture C60 effluent breakthrough curves and retention profiles observed in the column experiments. These findings indicate that Appling soil and Webster soil exhibit large retention capacity for C60 nanoparticle, and that transport of C60 is greatly enhanced in the presence of stabilizing agents.

  10. Modeling of the Transport and Retention of Fullerene C60 Aggregates in Porous Media

    Science.gov (United States)

    Li, Y.; Wang, Y.; Pennell, K.; Abriola, L.

    2008-12-01

    Buckminster fullerene (C60) has recently gained wide application in many commercial products. Given its widespread use, release of C60 into the environment during manufacture, transportation, and/or application is likely. Although C60 has negligible solubility in water, it is capable of acquiring charge and form highly stable nano-scale aggregates (nC60) in aqueous systems. In recent years, several laboratory research efforts have been devoted to studying the potential fate and transport of nC60 in porous media representative of the natural subsurface environment. Traditional clean-bed filtration theory is typically applied to analyze the experimental results. Far less attention has focused on the applicability of filtration theory to nC60 transport under different soil and solution conditions. In this work, we simulate column transport of nC60 under progressively more complex conditions and compare with laboratory observations. For nC60 transport in columns packed with Ottawa sand and simple electrolyte solutions, i.e. 1mM CaCl2 and 1mM NaCl, simulation results reveal that traditional clean-bed filtration theory is not sufficient to model the asymmetric breakthrough curves and relatively flat retention profiles observed in these systems. Modification of the filtration model, incorporating a maximum retention capacity term, can provide remarkably improved modeling results. The second application is for transport of nC60 in Ottawa sand coated with surfactant. The observed retention profiles in these experiments exhibit a hyper-exponential feature. Modeling results demonstrate that coupled simulation of both surfactant and nC60 transport is required to correctly capture the hyper-exponential retention profile in these systems. Finally, efforts to model the transport of nC60 in real soils, including Appling and Webster soils, are presented, suggesting that modification of filtration theory is also necessary in this case, to capture the shape of the observed retention

  11. Extraterrestrial Helium (He@C60) Trapped in Fullerenes in the Sudbury Impact Structure

    Science.gov (United States)

    Becker, L.; Bada, J. L.; Poreda, R. J.; Bunch, T. E.

    1997-01-01

    Fullerenes (C60 and C70) have recently been identified in a shock-produced breccia (Onaping Formation) associated with the 1.85-Ga Sudbury Impact Crater. The presence of parts-per-million levels of fullerenes in this impact structure raises interesting questions about the processes that led to the formation of fullerenes and the potential for delivery of intact organic material to the Earth by a large bolide (e.g., asteroid or comet). Two possible scenarios for the presence of fullerenes in the Sudbury impact deposits are that (1) fullerenes are synthesized within the impact plume from the C contained in the bolide; or (2) fullerenes are already present in the bolide and survived the impact event. The correlation of C and trapped noble gas atoms in meteorites is well established. Primitive meteorites contain several trapped noble gas components that have anomalous isotopic compositions, some of which may have a presolar origin. Several C-bearing phases, including SiC, graphite, and diamond, have been recognized as carriers of trapped noble gases. It has also been suggested that fullerenes (C60 and C70) might be a carrier of noble gas components in carbonaceous chondrites. Recently, fullerenes have been detected in separate samples in the Allende meteorite. Carbon-60 is large enough to enclose the noble gases He, Ne, Ar, Kr, and Xe, but it is too small to contain diatomic gases such as N2 or triatomic gases such as CO2. Recent experimental work has demonstrated that noble gases of a specific isotopic composition can be introduced into synthetic fullerenes at high temperatures and pressures; these encapsulated gases can then be released by the breaking of one or more C bonds during step-heating under vacuum. These thermal-release patterns for He encapsulated within the C60 molecule (He@C60) are similar to the patterns for acid residues of carbonaceous chondrites, suggesting that fullerenes could be an additional carrier of trapped noble gases in acid residues of

  12. Extraterrestrial Helium (He@C60) Trapped in Fullerenes in the Sudbury Impact Structure

    Science.gov (United States)

    Becker, L.; Bada, J. L.; Poreda, R. J.; Bunch, T. E.

    1997-01-01

    Fullerenes (C60 and C70) have recently been identified in a shock-produced breccia (Onaping Formation) associated with the 1.85-Ga Sudbury Impact Crater. The presence of parts-per-million levels of fullerenes in this impact structure raises interesting questions about the processes that led to the formation of fullerenes and the potential for delivery of intact organic material to the Earth by a large bolide (e.g., asteroid or comet). Two possible scenarios for the presence of fullerenes in the Sudbury impact deposits are that (1) fullerenes are synthesized within the impact plume from the C contained in the bolide; or (2) fullerenes are already present in the bolide and survived the impact event. The correlation of C and trapped noble gas atoms in meteorites is well established. Primitive meteorites contain several trapped noble gas components that have anomalous isotopic compositions, some of which may have a presolar origin. Several C-bearing phases, including SiC, graphite, and diamond, have been recognized as carriers of trapped noble gases. It has also been suggested that fullerenes (C60 and C70) might be a carrier of noble gas components in carbonaceous chondrites. Recently, fullerenes have been detected in separate samples in the Allende meteorite. Carbon-60 is large enough to enclose the noble gases He, Ne, Ar, Kr, and Xe, but it is too small to contain diatomic gases such as N2 or triatomic gases such as CO2. Recent experimental work has demonstrated that noble gases of a specific isotopic composition can be introduced into synthetic fullerenes at high temperatures and pressures; these encapsulated gases can then be released by the breaking of one or more C bonds during step-heating under vacuum. These thermal-release patterns for He encapsulated within the C60 molecule (He@C60) are similar to the patterns for acid residues of carbonaceous chondrites, suggesting that fullerenes could be an additional carrier of trapped noble gases in acid residues of

  13. Target Plate Material Influence on Fullerene-C60 Laser Desorption/Ionization Efficiency.

    Science.gov (United States)

    Zeegers, Guido P; Günthardt, Barbara F; Zenobi, Renato

    2016-04-01

    Systematic laser desorption/ionization (LDI) experiments of fullerene-C60 on a wide range of target plate materials were conducted to gain insight into the initial ion formation in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The positive and negative ion signal intensities of precursor, fragment, and cluster ions were monitored, varying both the laser fluence (0-3.53 Jcm(-2)) and the ion extraction delay time (0-950 ns). The resulting species-specific ion signal intensities are an indication for the ionization mechanisms that contribute to LDI and the time frames in which they operate, providing insight in the (MA)LDI primary ionization. An increasing electrical resistivity of the target plate material increases the fullerene-C60 precursor and fragment anion signal intensity. Inconel 625 and Ti90/Al6/V4, both highly electrically resistive, provide the highest anion signal intensities, exceeding the cation signal intensity by a factor ~1.4 for the latter. We present a mechanism based on transient electrical field strength reduction to explain this trend. Fullerene-C60 cluster anion formation is negligible, which could be due to the high extraction potential. Cluster cations, however, are readily formed, although for high laser fluences, the preferred channel is formation of precursor and fragment cations. Ion signal intensity depends greatly on the choice of substrate material, and careful substrate selection could, therefore, allow for more sensitive (MA)LDI measurements. Graphical Abstract ᅟ.

  14. Target Plate Material Influence on Fullerene-C60 Laser Desorption/Ionization Efficiency

    Science.gov (United States)

    Zeegers, Guido P.; Günthardt, Barbara F.; Zenobi, Renato

    2016-04-01

    Systematic laser desorption/ionization (LDI) experiments of fullerene-C60 on a wide range of target plate materials were conducted to gain insight into the initial ion formation in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The positive and negative ion signal intensities of precursor, fragment, and cluster ions were monitored, varying both the laser fluence (0-3.53 Jcm-2) and the ion extraction delay time (0-950 ns). The resulting species-specific ion signal intensities are an indication for the ionization mechanisms that contribute to LDI and the time frames in which they operate, providing insight in the (MA)LDI primary ionization. An increasing electrical resistivity of the target plate material increases the fullerene-C60 precursor and fragment anion signal intensity. Inconel 625 and Ti90/Al6/V4, both highly electrically resistive, provide the highest anion signal intensities, exceeding the cation signal intensity by a factor ~1.4 for the latter. We present a mechanism based on transient electrical field strength reduction to explain this trend. Fullerene-C60 cluster anion formation is negligible, which could be due to the high extraction potential. Cluster cations, however, are readily formed, although for high laser fluences, the preferred channel is formation of precursor and fragment cations. Ion signal intensity depends greatly on the choice of substrate material, and careful substrate selection could, therefore, allow for more sensitive (MA)LDI measurements.

  15. In silico properties characterization of water-soluble γ-cyclodextrin bi-capped C60 complex

    DEFF Research Database (Denmark)

    Cao, Ruyin; Wu, Shanshan

    2015-01-01

    Cyclodextrin-related host-guest encapsulation is pivotal to modulate the solubility of C60, thereby promoting its potential therapeutic applications. Here we present a computational study on γ-cyclodextrin bi-capped C60 complex, probing characteristics for all the possible stoichiometry in aqueous...

  16. Linear pi-conjugated systems derivatized with C60-fullerene as molecular heterojunctions for organic photovoltaics.

    Science.gov (United States)

    Roncali, Jean

    2005-06-01

    This tutorial review covers recent contributions in the area of linear pi-conjugated systems bound to fullerenes in view of their application as active materials in photovoltaic devices. The first part discusses the concepts of double-cable polymer and molecular hetero-junction and presents several examples of chemically or electrochemically synthesized C60-derivatized conjugated polymers. The second and main part of the article concerns the various classes of C60-derivatized pi-conjugated oligomers designed in view of their utilization in single-component photovoltaic devices. Thus, C60-containing pi-conjugated systems such as oligoarylenevinylenes, oligoaryleneethynylenes and oligothiophenes are discussed on the basis of the relationships between molecular structure, photophysical properties and performances of the derived photovoltaic devices. A brief last section presents some recent examples of surface-attached molecular hetero-junctions based on self-assembled monolayers and discusses possible routes for future research.

  17. Removal of aqueous nC60 fullerene from water by low pressure membrane filtration.

    Science.gov (United States)

    Floris, R; Nijmeijer, K; Cornelissen, E R

    2016-03-15

    The potential environmental and health risks of engineered nanoparticles such as buckminsterfullerene C60 in water require their removal during the production of drinking water. We present a study focusing on (i) the removal mechanism and (ii) the elucidation of the role of the membrane pore size during removal of nC60 fullerene nanoparticle suspensions in dead-end microfiltration and ultrafiltration mimicking separation in real industrial water treatment plants. Membranes were selected with pore sizes ranging from 18 nm to 500 nm to determine the significance of the nC60 to membrane pore size ratio and the adsorption affinity between nC60 and membrane material during filtration. Experiments were carried out with a dead-end bench-scale system operated at constant flux conditions including a hydraulic backwash cleaning procedure. nC60 nanoparticles can be efficiently removed by low pressure membrane technology with smaller and, unexpectedly, also by mostly similar or larger pores than the particle size, although the nC60 filtration behaviour appeared to be different. The nC60 size to membrane pore size ratio and the ratio of the cake-layer deposition resistance to the clean membrane resistance, both play an important role on the nC60 filtration behaviour and on the efficiency of the backwash procedure recovering the initial membrane filtration conditions. These results become specifically significant in the context of drinking water production, for which they provide relevant information for an accurate selection between membrane processes and operational parameters for the removal of nC60 in the drinking water treatment.

  18. Graphene oxide-fullerene C60 (GO-C60) hybrid for photodynamic and photothermal therapy triggered by near-infrared light.

    Science.gov (United States)

    Li, Qian; Hong, Liang; Li, Hongguang; Liu, Chenguang

    2017-03-15

    Photodynamic therapy (PDT) and photothermal therapy (PTT) are two promising methodologies for cancer therapy. Although a variety of materials which can be used in PDT and PTT have been developed in the past decades, those showing the combined effect of PDT and PTT under NIR irradiation are rare. Graphene oxide (GO) and fullerene C60 (denoted as C60 hereafter) with unique physical and chemical properties are promising candidates for PTT and PDT, respectively. Here, by using a stepwise conjugation method, a new GO-C60 hybrid which contains hydrophilic methoxypolyethylene glycol (mPEG) and mono-substituted C60 was constructed for combined PDT and PTT. The hybrid shows good solubility in different environments including physiological solutions. The introduction of C60 to GO did not decrease the photothermal properties of GO, while the conjugation of GO to C60 activated the ability of C60 to generate singlet oxygen ((1)O2) in near infrared (NIR) region in aqueous solution. The GO-C60 hybrid also shows good ability to induce the generation of reactive oxygen species (ROS) in Hela cells. Due to the synergistic effect between GO and C60, GO-C60 hybrid exhibits superior performance in the inhibition of cancer cells compared to both individuals, indicating its high potential in practical applications.

  19. Production of Self-Assembled Fullerene (C60) Nanocrystals at Liquid-Liquid Interface.

    Science.gov (United States)

    Shrestha, Rekha Goswami; Shrestha, Lok Kumar; Abe, Masahiko; Ariga, Katsuhiko

    2015-03-01

    Here we present self-assembled nanostructure of functional molecule fullerene (C60) at liquid-liquid interface. The nanostructured nanocrystals were grown at liquid-liquid interface of isopropyl alcohol (IPA) and C60 solution in butylbenzene under ambient condition of temperature and pressure, and characterized by Raman scattering, power X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The crystal formation mechanism is driven by supersaturation related to the low solubility of C60 in IPA. A slow diffusion of IPA towards the C60 solution causes unsaturation of C60 at the liquid-liquid interface and consequently small clusters of C60 is formed at the interface, which acts as the nucleation site. Further diffusion of IPA supplies the C60 molecules from bulk to the interface promoting the crystal growth. Based on SEM and TEM observation, the average size of the individual hexagonal bipyramid nanocrystal is found to be ca. 1.4 µm and the average size of their assembly is found to be approximately 2 µm. XRD measurements have shown that these materials are crystalline with mixed face-centered cubic (cell dimension: a = 1.352 nm, and V = 2.475 nm3) and hexagonal (cell dimension: a = 1.452 nm, c = 1.207 nm, c/a = 0.831, and V = 2.475 nm3) structures. Raman scattering measurements showed two Ag and six Hg vibration bands, which are similar to those obtained in the pristine C60.

  20. Aggregation behavior of fullerenes in aqueous solutions: a capillary electrophoresis and asymmetric flow field-flow fractionation study

    NARCIS (Netherlands)

    A. Astefanei; O. Núñez; M.T. Galceran; W.Th. Kok; P.J. Schoenmakers

    2015-01-01

    In this work, the electrophoretic behavior of hydrophobic fullerenes [buckminsterfullerene (C-60), C-70, and N-methyl-fulleropyrrolidine (C-60-pyrr)] and water-soluble fullerenes [fullerol (C-60(OH)(24)); polyhydroxy small gap fullerene, hydrated (C-120(OH)(30)); C-60 pyrrolidine tris acid (C-60-pyr

  1. Self assembly of amphiphilic C60 fullerene derivatives into nanoscale supramolecular structures

    Directory of Open Access Journals (Sweden)

    Casscells S Ward

    2007-08-01

    Full Text Available Abstract Background The amphiphilic fullerene monomer (AF-1 consists of a "buckyball" cage to which a Newkome-like dendrimer unit and five lipophilic C12 chains positioned octahedrally to the dendrimer unit are attached. In this study, we report a novel fullerene-based liposome termed 'buckysome' that is water soluble and forms stable spherical nanometer sized vesicles. Cryogenic electron microscopy (Cryo-EM, transmission electron microscopy (TEM, and dynamic light scattering (DLS studies were used to characterize the different supra-molecular structures readily formed from the fullerene monomers under varying pH, aqueous solvents, and preparative conditions. Results Electron microscopy results indicate the formation of bilayer membranes with a width of ~6.5 nm, consistent with previously reported molecular dynamics simulations. Cryo-EM indicates the formation of large (400 nm diameter multilamellar, liposome-like vesicles and unilamellar vesicles in the size range of 50–150 nm diameter. In addition, complex networks of cylindrical, tube-like aggregates with varying lengths and packing densities were observed. Under controlled experimental conditions, high concentrations of spherical vesicles could be formed. In vitro results suggest that these supra-molecular structures impose little to no toxicity. Cytotoxicity of 10–200 μM buckysomes were assessed in various cell lines. Ongoing studies are aimed at understanding cellular internalization of these nanoparticle aggregates. Conclusion In this current study, we have designed a core platform based on a novel amphiphilic fullerene nanostructure, which readily assembles into supra-molecular structures. This delivery vector might provide promising features such as ease of preparation, long-term stability and controlled release.

  2. Electrodynamical Forbiddance of the Strong Quadrupole Light-Molecule Interaction and Its Experimental Manifestation in Fullerene C60

    CERN Document Server

    Chelibanov, V P

    2016-01-01

    It is demonstrated that the forbidden lines, which must be present in the SERS, TERS and SEIRA spectra of molecules with sufficiently high symmetry, associated with a strong quadrupole light-molecule interaction, are absent in the fullerene C60. This result is an experimental manifestation of an electrodynamical forbiddance of the strong quadrupole light-molecule interaction, which must be not only in molecules with cubic symmetry groups, but in the fullerene C60 also.

  3. Organic field effect transistor composed by fullerene C60 and heterojunctions

    Science.gov (United States)

    Vasconcelos, Railson C.; Aleixo, Vicente F. P.; Del Nero, Jordan

    2017-02-01

    We present a study of the complex electronic behavior of a fullerene (C60) molecule attached to six leads (heterojunctions), which works as a three-dimension rectifier. In addition, we confirmed that the fullerene works not only as an electron donor, but also as barrier and transport channel to electrons through the molecule. Moreover, when the phenylpropanodinilla (PPP) lead is orthogonally subjected to bias voltage, the charge distribution and the current displays regions of saturation and resonance similar to semiconductor devices. In order to understand the electronic transport in the molecule, we applied non-equilibrium green function (NEGF) method and performed Fowler-Nordheim (FN) and Millikan-Lauritsen (ML) analyses. The ML curves proved to be sufficient to describe the FN characteristics. In this work, we report the theoretical design for electronic transport of a 3D device (6-terminal).

  4. Continuum modeling investigation of gigahertz oscillators based on a C60 fullerene inside cyclic peptide nanotubes

    Science.gov (United States)

    Sadeghi, F.; Ansari, R.; Darvizeh, M.

    2016-02-01

    Research concerning the fabrication of nano-oscillators with operating frequency in the gigahertz (GHz) range has become a focal point in recent years. In this paper, a new type of GHz oscillators is introduced based on a C60 fullerene inside a cyclic peptide nanotube (CPN). To study the dynamic behavior of such nano-oscillators, using the continuum approximation in conjunction with the 6-12 Lennard-Jones (LJ) potential function, analytical expressions are derived to determine the van der Waals (vdW) potential energy and interaction force between the two interacting molecules. Employing Newton's second law, the equation of motion is solved numerically to arrive at the telescopic oscillatory motion of a C60 fullerene inside CPNs. It is shown that the fullerene molecule exhibits different kinds of oscillation inside peptide nanotubes which are sensitive to the system parameters. Furthermore, for the precise evaluation of the oscillation frequency, a novel semi-analytical expression is proposed based on the conservation of the mechanical energy principle. Numerical results are presented to comprehensively study the effects of the number of peptide units and initial conditions (initial separation distance and velocity) on the oscillatory behavior of C60 -CPN oscillators. It is found out that for peptide nanotubes comprised of one unit, the maximum achievable frequency is obtained when the inner core oscillates with respect to its preferred positions located outside the tube, while for other numbers of peptide units, such frequency is obtained when the inner core oscillates with respect to the preferred positions situated in the space between the two first or the two last units. It is further found out that four peptide units are sufficient to obtain the optimal frequency.

  5. Ionization energies of the C60 fullerene and its hydrogenated derivatives C60H18 and C60H36 determined by electron ionization

    Science.gov (United States)

    Pogulay, Andrey V.; Abzalimov, Rinat R.; Nasibullaev, Shamil'k.; Lobach, Anatoly S.; Drewello, Thomas; Vasil'Ev, Yury V.

    2004-04-01

    Modification of a method for processing positive ion ionization efficiency curves of polyatomic molecules, as developed earlier by Märk and coworkers, has been described. Based on the method, the first, second, and third ionization energies of C60 have been re-examined and found to be in excellent agreement with the most reliable literature data. The ionization energies for C60H18 and C60H36 have been measured for the first time and were established as 7.3+/-0.3 eV and 7.01+/-0.25 eV, respectively. Although the appearance energy of C60H362+ (18.7+/-0.2 eV) has been determined to be lower than that of C602+ (18.98+/-0.35 eV), the reverse scenario is true for the second ionization energies of C60H36 and C60.

  6. Formation of a new adduct based on fullerene tris-malonate samarium salt C60-[C60(=C(COO)2)3]Sm2

    Science.gov (United States)

    Petrov, A. A.; Keskinov, V. A.; Semenov, K. N.; Charykov, N. A.; Letenko, D. G.; Nikitin, V. A.

    2017-03-01

    Gram quantities of a new adduct based on light fullerene tris-malonate samarium salt C60 [C60(=C(COO)2)3]Sm2 are obtained via the reaction of ion exchange. The obtained adduct is studied by means of electron and infrared spectroscopy, X-ray and elemental analysis, electron microscopy, and thermogravimetry. The polythermal solubility of [C60(=C(COO)2)3]Sm2 in water is determined in ampoules via saturation within 20-70°C. The composition of crystalline hydrate [C60(=C(COO)2)3]Sm2 · 36H2O, which exists in equilibrium with the saturated solution, is estimated.

  7. Change of 7Be decay rate in exohedral and endohedral C60 fullerene compounds and its implications

    CERN Document Server

    Ray, A; Saha, S K; Das, S K; Das, J J; Madhavan, N; Nath, S; Sugathan, P; Rao, P V M; Jhingan, A

    2006-01-01

    The half-life of 7Be implanted in a C60 pellet and gold foil has been measured to be about the same within about 0.2%. Using a radiochemical technique, we also measured that the probability of formation of endohedral 7Be@C60 by nuclear implantation technique was (5.6+-0.45)%. It is known from earlier works that the half-life of endohedral 7Be@C60 is about 1.2% shorter than that of 7Be implanted in gold. An analysis of these results using linear muffin-tin orbital method calculations indicates that most of the implanted 7Be ions in fullerene C60 stay at a distance of about 5.3 Angstrom from the centers of nearest C60 molecules forming exohedral compounds and those who enter the fullerene cages go to the centers of the cages forming endohedral 7Be@C60 compounds.

  8. Contaminant-mobilizing capability of fullerene nanoparticles (nC60): Effect of solvent-exchange process in nC60 formation.

    Science.gov (United States)

    Wang, Lilin; Fortner, John D; Hou, Lei; Zhang, Chengdong; Kan, Amy T; Tomson, Mason B; Chen, Wei

    2013-02-01

    Fullerene nanoparticles (nC(60)) in aqueous environments can significantly enhance the transport of hydrophobic organic contaminants by serving as a contaminant carrier. In the present study, the authors examine the effect of the solvent-exchange process on nC(60) aggregate formation and, subsequently, on nC(60) 's contaminant-mobilizing capability. A series of nC(60) samples were prepared using a modified toluene-water solvent-exchange method through the inclusion of a secondary organic solvent in the phase transfer of molecular C(60) in toluene to nC(60) in water. Two groups of solvents--a water-miscible group and a non-water-miscible group-of varied polarity were selected as secondary solvents. The involvement of a secondary solvent in the phase transfer process had only small effects on the particle size and distribution, ζ potential, and mobility of the nC(60) products but significantly influenced the capability of nC(60) to enhance the transport of 2,2',5,5'-polychlorinated biphenyl (PCB) in a saturated sandy soil column, regardless of whether the secondary solvent was water-miscible or non-water-miscible. The two groups of secondary solvents appear to affect the aggregation properties of nC(60) in water via different mechanisms. In general, nC(60) products made with a secondary water-miscible solvent have stronger capabilities to enhance PCB transport. Taken together, the results indicate that according to formation conditions and solvent constituents, nC(60) will vary significantly in its interactions with organic contaminants, specifically as related to adsorption or desorption as well as transport in porous media.

  9. Aggregation behavior of fullerenes in aqueous solutions: a capillary electrophoresis and asymmetric flow field-flow fractionation study

    NARCIS (Netherlands)

    Astefanei, A.; Núñez, O.; Galceran, M.T.; Kok, W.Th.; Schoenmakers, P.J.

    2015-01-01

    In this work, the electrophoretic behavior of hydrophobic fullerenes [buckminsterfullerene (C-60), C-70, and N-methyl-fulleropyrrolidine (C-60-pyrr)] and water-soluble fullerenes [fullerol (C-60(OH)(24)); polyhydroxy small gap fullerene, hydrated (C-120(OH)(30)); C-60 pyrrolidine tris acid

  10. CORAL: QSPR models for solubility of [C60] and [C70] fullerene derivatives.

    Science.gov (United States)

    Toropova, Alla P; Toropov, Andrey A; Benfenati, Emilio; Gini, Giuseppina; Leszczynska, Danuta; Leszczynski, Jerzy

    2011-02-01

    Quantitative structure-property relationships (QSPRs) between the molecular structure of [C(60)] and [C(70)] fullerene derivatives and their solubility in chlorobenzene (mg/mL) have been established by means of CORAL (CORrelations And Logic) freeware. The CORAL models are based on representation of the molecular structure by simplified molecular input line entry system (SMILES). Three random splits into the training and the external validation sets have been examined. The ranges of statistical characteristics of these models are as follows: n = 18, r (2) = 0.748-0.815, s = 15.1 -17.5 (mg/mL), F = 47-71 (training set); n = 9, r (2) = 0.806-0.936, s = 12.5-17.5 (mg/mL), F = 29-103 (validation set).

  11. Synthesis and Characterization of Fullerene Nanowhiskers by Liquid-Liquid Interfacial Precipitation: Influence of C60 Solubility

    Directory of Open Access Journals (Sweden)

    Marappan Sathish

    2012-03-01

    Full Text Available Fullerene nanowhiskers (FNWs composed of C60 fullerene molecules were prepared using the liquid–liquid interfacial precipitation (LLIP method in the carbon-disulfide (CS2 and isopropyl alcohol (IPA system. The electron microscopic images reveal the formation of non-tubular FNWs. The X-ray diffraction (XRD pattern studies indicate the presence of fcc crystalline structure and unusual triclinic structure in the FNWs. The selected area electron diffraction pattern (SAED analysis demonstrates the existence of triclinic and electron beam assisted fcc to tetragonal crystalline phase transformation. The formation of triclinic structure might be validated due to the partial polymerization of FNWs at C60 saturated CS2-IPA interface. The high solubility of C60 in CS2 solvent system results in partial polymerization of FNWs. The polymerization of fullerene molecules in the FNWs has been further confirmed using Raman spectroscopy.

  12. In Silico Study of Spacer Arm Length Influence on Drug Vectorization by Fullerene C60

    Directory of Open Access Journals (Sweden)

    Haifa Khemir

    2015-01-01

    Full Text Available This work studies theoretically the effect of spacer arm lengths on the characteristics of a fullerene C60-based nanovector. The spacer arm is constituted of a carbon chain including a variable number of methylene groups (n = 2–11. To improve the ability of the fullerene carriage, two arms are presented simultaneously through a malonyl bridge. Then the evolution of selected physicochemical parameters is monitored as a function of the spacer arm length and the angle between the two arms. We show here that while the studied characteristics are almost independent of the spacer arm length or vary monotonically with it, the dipole moment and its orientation vary periodically with the parity of the number of carbon atoms. This periodicity is related to both modules and orientations of dipole moments of the spacer arms. In the field of chemical synthesis, these results highlight the importance of theoretical calculations for the optimization of operating conditions. In the field of drug discovery, they show that theoretical calculations of the chemical properties of a drug candidate can help predict its in vivo behaviour, notably its bioavailability and biodistribution, which are known to be tightly dependent of its polarity.

  13. Efficient and Convenient Preparation of Water-Soluble Fullerenol

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-Min章建民; YANG Wen杨文; HE Ping何萍; ZHU Shi-Zheng朱士正

    2004-01-01

    An efficient and convenient preparation of fullerenols was described. With polyethylene glycol (PEG) 400 as catalyst, fullerenols were conveniently synthesized via the direct reaction of fullerene with aqueous NaOH. By control of reaction conditions, either water-soluble C60 fullerenol or water-insoluble C60 fullerenol could be obtained selectively.

  14. Clinical evaluation of fullerene-C60 dissolved in squalane for anti-wrinkle cosmetics.

    Science.gov (United States)

    Kato, Shinya; Taira, Hikaru; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2010-10-01

    Highly purified and organic solvent-free fullerene-C60 was dissolved, at nearly saturated concentration of 278 ppm, in squalane prepared from olive oil, which is designated as LipoFullerene (LF-SQ) and was examined for usage as a cosmetic ingredient with antioxidant ability. The aim of this study was to assess the anti-wrinkle formation efficacy of LF-SQ in subjects. A total of 23 Japanese women (group I: age 38.9 +/- 3.8, n = 11, group II; age 39.4 +/- 4.3, n = 12) were enrolled in an 8-week trial of LF-SQ blended cream in a randomized, matched pair double-blind study. The LF-SQ cream was applied twice daily on the right or left half of the face, and squalane blended cream (without fullerene-C60) was applied as the placebo on another half of the face. As clinical evaluations of wrinkle grades, visual observation and photographs, and silicone replicas of both crow's feet areas were taken at baseline (0 week) and at 4th and 8th weeks. Skin replicas were analyzed using an optical profilometry technique. The wrinkle and skin-surface roughness features were calculated and statistically analyzed. Subsequently, trans-epidermal water loss (TEWL), moisture levels of the stratum corneum, and visco-elasticity (suppleness: RO and elasticity: R7) were measured on cheeks by instrumental analysis. LF-SQ cream enhanced the skin moisture and the anti-wrinkle formation. LF-SQ cream that was applied on a face twice daily was not effective at 4th week, but significantly more effective than the placebo at 8th week (p < 0.05) without severe side effects. The roughness-area ratio showed significant improvement (p < 0.05) at 8th week with LF-SQ cream as compared to 0 week with LF-SQ cream, but no significant difference was detected between LF-SQ cream and the placebo. We suggest that LF-SQ could be used as an active ingredient for wrinkle-care cosmetics.

  15. Strong-field effects in the photo-emission spectrum of the C$_{60}$ fullerene

    CERN Document Server

    Gao, Cong-Zhang; Kluepfel, Peter; Meier, Chris; Reinhard, Paul-Gerhard; Suraud, Eric

    2016-01-01

    Considering C$_{60}$ as a model system for describing field emission from the extremity of a carbon nanotip, we explore electron emission from this fullerene excited by an intense, near-infrared, few-cycle laser pulse ($10^{13}$-$10^{14}~{\\rm W/cm}^2$, 912 nm, 8-cycle). To this end, we use time-dependent density functional theory augmented by a self-interaction correction. The ionic background of C$_{60}$ is described by a soft jellium model. Particular attention is paid to the high energy electrons. Comparing the spectra at different emission angles, we find that, as a major result of this study, the photoelectrons are strongly peaked along the laser polarization axis forming a highly collimated electron beam in the forward direction, especially for the high energy electrons. Moreover, the high-energy plateau cut-off found in the simulations agrees well with estimates from the classical three-step model. We also investigate the build-up of the high-energy part of a photoelectron spectrum by a time-resolved a...

  16. C60 Fullerene as Promising Therapeutic Agent for the Prevention and Correction of Skeletal Muscle Functioning at Ischemic Injury

    Science.gov (United States)

    Nozdrenko, D. M.; Zavodovskyi, D. O.; Matvienko, T. Yu.; Zay, S. Yu.; Bogutska, K. I.; Prylutskyy, Yu. I.; Ritter, U.; Scharff, P.

    2017-02-01

    The therapeutic effect of pristine C60 fullerene aqueous colloid solution (C60FAS) on the functioning of the rat soleus muscle at ischemic injury depending on the time of the general pathogenesis of muscular system and method of administration C60FAS in vivo was investigated. It was found that intravenous administration of C60FAS is the optimal for correction of speed macroparameters of contraction for ischemic muscle damage. At the same time, intramuscular administration of C60FAS shows pronounced protective effect in movements associated with the generation of maximum force responses or prolonged contractions, which increase the muscle fatigue level. Analysis of content concentration of creatine phosphokinase and lactate dehydrogenase enzymes in the blood of experimental animals indicates directly that C60FAS may be a promising therapeutic agent for the prevention and correction of ischemic-damaged skeletal muscle function.

  17. Fullerene-C60 and crown ether doped on C60 sensors for high sensitive detection of alkali and alkaline earth cations

    Science.gov (United States)

    Zaghmarzi, Fatemeh Alipour; Zahedi, Mansour; Mola, Adeleh; Abedini, Saboora; Arshadi, Sattar; Ahmadzadeh, Saeed; Etminan, Nazanin; Younesi, Omran; Rahmanifar, Elham; Yoosefian, Mehdi

    2017-03-01

    Fullerenes are effective acceptor components with high electron affinity for charge transfer. The significant influences of chemical adsorption of the cations on the electrical sensitivity of pristine C60 and 15-(C2H4O)5/C60 nanocages could be the basis of new generation of electronic sensor design. The density functional theory calculation for alkali and alkaline earth cations detection by pristine C60 and 15-(C2H4O)5/C60 nanocages are considered at B3LYP level of theory with 6-31 G(d) basis set. The quantum theory of atoms in molecules analysis have been performed to understand the nature of intermolecular interactions between the cations and nanocages. Also, the natural bond orbital analysis have been performed to assess the intermolecular interactions in detail. Furthermore, the frontier molecular orbital, energy gap, work function, electronegativity, number of transferred electron (∆N), dipole moment as well as the related chemical hardness and softness are investigated and calculated in this study. The results show that the adsorption of cations (M=Na+, K+, Mg2+ and Ca2+) are exothermic and the binding energy in pristine C60 nanocage and 15-(C2H4O)5/C60 increases with respect to the cations charge. The results also denote a decrease in the energy gap and an increase in the electrical conductivity upon the adsorption process. In order to validate the obtained results, the density of state calculations are employed and presented in the end as well.

  18. Dipole polarizability, structure, and stability of [2+2]-linked fullerene nanostructures (C60)n (n≤7)

    Science.gov (United States)

    Pankratyev, Evgeniy Yu.; Tukhbatullina, Alina A.; Sabirov, Denis Sh.

    2017-02-01

    In the present work, structural features, dipole polarizability, and stability of two most promising oligomeric series (C60)n with zigzag and linear arrangement of the fullerene cages have been studied by the PBE/3ζ density functional theory method. Their mean polarizabilities and polarizability exaltations are linearly correlated with the molecular size (maximal intercage distance). Linear (C60)n have higher polarizability than zigzag oligomers with the same n. Based on the example of hexamers (C60)6, we have shown that connectivity (number of connections) has no effect on the resulting polarizability but maximal remoteness does, i.e. the geometric factor is more decisive for mean polarizability of such fullerene nanostructures. Stability of (C60)n decreases with growing molecular size for linear structures and slowly increases in the case of zigzag (C60)n. The found dependences of polarizability and stability on the molecular size may be used for assessing these parameters of larger fullerene nanostructures, hardly computable with quantum chemical methods.

  19. Analysis of C60-fullerene derivatives and pristine fullerenes in environmental samples by ultrahigh performance liquid chromatography-atmospheric pressure photoionization-mass spectrometry.

    Science.gov (United States)

    Astefanei, Alina; Núñez, Oscar; Galceran, Maria Teresa

    2014-10-24

    In this work, a method is proposed for the simultaneous analysis of several pristine fullerenes (C60, C70, C76, C78, and C84) and three C60-fullerene derivatives (N-methyl fulleropyrrolidine, [6,6]-phenyl C61 butyric acid methyl ester and [6,6]-phenyl C61 butyric acid butyl ester) in environmental samples. The method involves the use of ultrahigh performance liquid chromatography coupled to atmospheric pressure photoionization mass spectrometry (UHPLC-APPI-MS) and allowed the chromatographic separation in less than 4.5min. The product ions from tandem mass spectrometry studies of fullerene derivatives were characterized and the most abundant one (m/z 720), corresponding to [C60](-), was selected for quantitation. Selected reaction monitoring (SRM at 0.7m/z FWHM) by acquiring two transitions using both isotopic cluster ions [M](-) and [M+1](-) as precursor ions was proposed for quantitation and confirmation purposes. For pristine fullerenes, highly selective selected ion monitoring (H-SIM) acquisition mode by monitoring the isotopic cluster ions [M](-) and [M+1](-) was used. Pressurized solvent extraction conditions were optimized in order to improve recoveries of the studied fullerene compounds from sediment samples. Values up to 87-92% for C60-fullerene derivatives and lower but still acceptable, 70-80%, for pristine fullerenes were obtained. Method limits of quantitation (MLOQs) ranging from 1.5pgL(-1) to 5.5ngL(-1) in water samples and from 0.1ngkg(-1) to 523ngkg(-1) in sediments were obtained with good precision (relative standard deviations always lower than 13%). The applicability of the developed method was evaluated by analyzing several environmental samples such as sediments and pond water and the detected levels for C60-fullerene derivatives were of 0.1-2.7ngkg(-1) and 1.5-8.5pgL(-1), respectively. C60 and C70 were the only pristine fullerenes detected in the analyzed samples (0.1-7.2ngkg(-1) in sediments and 9-330pgL(-1) in water pond samples). Copyright

  20. Femtosecond dynamics of correlated many-body states in C60 fullerenes

    Science.gov (United States)

    Usenko, Sergey; Schüler, Michael; Azima, Armin; Jakob, Markus; Lazzarino, Leslie L.; Pavlyukh, Yaroslav; Przystawik, Andreas; Drescher, Markus; Laarmann, Tim; Berakdar, Jamal

    2016-11-01

    Fullerene complexes may play a key role in the design of future molecular electronics and nanostructured devices with potential applications in light harvesting using organic solar cells. Charge and energy flow in these systems is mediated by many-body effects. We studied the structure and dynamics of laser-induced multi-electron excitations in isolated C60 by two-photon photoionization as a function of excitation wavelength using a tunable fs UV laser and developed a corresponding theoretical framework on the basis of ab initio calculations. The measured resonance line width gives direct information on the excited state lifetime. From the spectral deconvolution we derive a lower limit for purely electronic relaxation on the order of {τ }{el}={10}-3+5 fs. Energy dissipation towards nuclear degrees of freedom is studied with time-resolved techniques. The evaluation of the nonlinear autocorrelation trace gives a characteristic time constant of {τ }{vib}=400+/- 100 fs for the exponential decay. In line with the experiment, the observed transient dynamics is explained theoretically by nonadiabatic (vibronic) couplings involving the correlated electronic, the nuclear degrees of freedom (accounting for the Herzberg-Teller coupling), and their interplay.

  1. Femtosecond dynamics of correlated many-body states in C$_{60}$ fullerenes

    CERN Document Server

    Usenko, Sergey; Azima, Armin; Jakob, Markus; Lazzarino, Leslie L; Pavlyukh, Yaroslav; Przystawik, Andreas; Drescher, Markus; Laarmann, Tim; Berakdar, Jamal

    2016-01-01

    Fullerene complexes may play a key role in the design of future molecular electronics and nanostructured devices with potential applications in light harvesting using organic solar cells. Charge and energy flow in these systems is mediated by many-body effects. We studied the structure and dynamics of laser-induced multi-electron excitations in isolated C$_{60}$ by two-photon photoionization as a function of excitation wavelength using a tunable fs UV laser and developed a corresponding theoretical framework on the basis of ab initio calculations. The measured resonance line width gives direct information on the excited state lifetime. From the spectral deconvolution we derive a lower limit for purely electronic relaxation on the order of $\\tau_\\mathrm{el}=8^{+12}_{-5}$ fs. Energy dissipation towards nuclear degrees of freedom is studied in time-resolved experiments. The evaluation of the non-linear autocorrelation trace gives a characteristic time constant of $\\tau_\\mathrm{vib}=309\\pm31$ fs for the exponenti...

  2. Determination of Fullerenes (C60/C70) from the Permian-Triassic Boundary in the Meishan Section of South China

    Institute of Scientific and Technical Information of China (English)

    LI Yanfang; LIANG Handong; YIN Hongfu; SUN Jing; CAI Hou'an; RAO Zhu; RAN Fanlin

    2005-01-01

    Fullerenes (C60/C70), clays and rocks near the Permian-Triassic (P/T) boundary in the Meishan section of South China are explored by means of comprehensive analytical techniques, including ultrasonic extraction with column purification, high-performance liquid chromatography (HPLC) and matrix assisted laser desorption/ionization time-offlight mass spectrometry (MALDI TOF MS). The study confirms the existence of fullerenes toward the P/T event boundary and their absence in clays and limestones beyond the boundary. In particular, the white clay, known as the event boundary, contains fullerenes of 0.33 ppb, while the red material, as the first lamina fill of goethite and gypsum on the base of the white clay, contains fullerenes of 1.23 ppb, and the last lamina of 2.50 ppb. Significantly, distinct enrichment of fullerenes is coincident with the disappearance of fossil records of marine species (94%) just at the base of the white clay,implying that geological fullerenes would be one of temporal remnants led by the P/T catastrophic event. This work strongly supports that fullerenes would be one of significant records of the P/T catastrophic event but their origin remains to be studied further.

  3. ‘Horror vacui’ or topological in-out isomerism in perhydrogenated fullerenes: C60H60 and monoalkylated perhydrogenated fullerenes

    Science.gov (United States)

    Dodziuk, Helena; Nowinski, Krzysztof

    1996-02-01

    In endohedral chemistry, one of the exciting prospects offered by the cage-like structure of fullerenes, several aspects of the calculations on in-out isomerism of perhydrogenated fullerene and their consequences went unnoticed, e.g. the topological character of the isomerism, the instability of C 60F 60, which was thought to revolutionize industry as an ideal lubricant, as well as the possibility of in-out isomerism in alkylated fulleranes. Molecular mechanics calculations indicate that for smaller alkyl groups the 'in' isomer is significantly more stable extending the possibility of endohedral fullerene chemistry. C 60H 60 and its derivatives can be considered as examples of a manifestation of the ancient 'horror vacui' concept.

  4. Influence of fullerene (C60) on soil bacterial communities: aqueous aggregate size and solvent co-introduction effects

    Science.gov (United States)

    Tong, Zhong-Hua; Bischoff, Marianne; Nies, Loring F.; Carroll, Natalie J.; Applegate, Bruce; Turco, Ronald F.

    2016-06-01

    Fullerene C60 nanoparticles are being used in broad range of applications. It is important to assess their potential impacts in the environment. We evaluated the effects of C60 introduced as aqueous suspensions of nC60 aggregates of different particle size or via organic solvents on soils with different organic matter contents in this study. Impacts of the application were evaluated by measuring total microbial biomass, metabolic activity and bacterial community structure. Results show that nC60 aggregates, introduced as an aqueous suspension, had size-dependent effects on soil bacterial community composition in the low organic matter system, but induced minimal change in the microbial biomass and metabolic activity in soils with both high and low organic matter contents. Fullerene C60, co-introduced via an organic solvent, did not influence the response of soil microbes to the organic solvents. Our results suggest that nC60 aggregates of smaller size may have negative impact on soil biota and soil organic matter may play a key role in modulating the environmental effect of nanomaterials.

  5. Understanding the electronic structure of CdSe quantum dot-fullerene (C60) hybrid nanostructure for photovoltaic applications

    Science.gov (United States)

    Sarkar, Sunandan; Rajbanshi, Biplab; Sarkar, Pranab

    2014-09-01

    By using the density-functional tight binding method, we studied the electronic structure of CdSe quantum dot(QD)-buckminsterfullerene (C60) hybrid systems as a function of both the size of the QD and concentration of the fullerene molecule. Our calculation reveals that the lowest unoccupied molecular orbital energy level of the hybrid CdSeQD-C60 systems lies on the fullerene moiety, whereas the highest occupied molecular orbital (HOMO) energy level lies either on the QD or the fullerene depending on size of the CdSe QD. We explored the possibility of engineering the energy level alignment by varying the size of the CdSe QD. With increase in size of the QD, the HOMO level is shifted upward and crosses the HOMO level of the C60-thiol molecule resulting transition from the type-I to type-II band energy alignment. The density of states and charge density plot support these types of band gap engineering of the CdSe-C60 hybrid systems. This type II band alignment indicates the possibility of application of this nanohybrid for photovoltaic purpose.

  6. Encapsulation of C60 fullerenes into single-walled carbon nanotubes: Fundamental mechanical principles and conventional applied mathematical modeling

    Science.gov (United States)

    Baowan, Duangkamon; Thamwattana, Ngamta; Hill, James M.

    2007-10-01

    A well-known self-assembled hybrid carbon nanostructure is a nanopeapod which may be regarded as the prototype nanocarrier for drug delivery. While the investigation of the packing of C60 molecules inside a carbon nanotube is usually achieved through either experimentation or large scale computation, this paper adopts elementary mechanical principles and classical applied mathematical modeling techniques to formulate explicit analytical criteria and ideal model behavior for such encapsulation. In particular, we employ the Lennard-Jones potential and the continuum approximation to determine three encapsulation mechanisms for a C60 fullerene entering a tube: (i) through the tube open end (head-on), (ii) around the edge of the tube open end, and (iii) through a defect opening on the tube wall. These three encapsulation mechanisms are undertaken for each of the three specific carbon nanotubes (10,10), (16,16), and (20,20). We assume that all configurations are in vacuum and the C60 fullerene is initially at rest. Double integrals are performed to determine the energy of the system and analytical expressions are obtained in terms of hypergeometric functions. Our results suggest that the C60 fullerene is most likely to be encapsulated by head-on through the open tube end and that encapsulation around the tube edge is least likely to occur because of the large van der Waals energy barriers which exist at the tube ends.

  7. Single crystals of fullerene (C60 makes organic thick film solar cells and self supporting organic solar cells possible.

    Directory of Open Access Journals (Sweden)

    M. Umeno

    2008-06-01

    Full Text Available Single crystals of Fullerene (SC-C60 were synthesized by simple liquid/liquid interface precipitation method. Organic thick film solar cell (with an active layer thickness of approximately 20 microns thick is demonstrated by combining SC-C60 with poly(3-octylthiophene. Our preliminary results indicate that organic thick film solar cells are possible; which were considered to be impossible due to low mobility and small exciton diffusion lengths in most of the organic materials including small organic molecules and conjugated conducting polymers. Further, SC-C60 seems to be promising materials for organic photovoltaics. Self supporting organic solar cell is also demonstrated using SC-C60.

  8. Oxidatively damaged DNA in rats exposed by oral gavage to C60 fullerenes and single-walled carbon nanotubes

    DEFF Research Database (Denmark)

    Folkmann, Janne K; Risom, Lotte; Jacobsen, Nicklas R

    2009-01-01

    BACKGROUND: C60 fullerenes and single-walled carbon nanotubes (SWCNT) are projected to be used in medicine and consumer products with potential human exposure. The hazardous effects of these particles are expected to involve oxidative stress with generation of oxidatively damaged DNA that might...... be the initiating event in the development of cancer. OBJECTIVE: In this study we investigated the effect of a single oral administration of C60 fullerenes and SWCNT. METHODS: We measured the level of oxidative damage to DNA as the premutagenic 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) in the colon mucosa...... the levels of 8-oxodG in liver and lung. Administration of C60 fullerenes increased the hepatic level of 8-oxodG, whereas only the high dose generated 8-oxodG in the lung. We detected no effects on 8-oxodG in colon mucosa. Suspension of particles in saline solution or corn oil yielded a similar extent...

  9. COMBINED EFFECT OF ELECTROMAGNETIC RADIATION, DNA-INTERCALATORS, C60-FULLERENE AND CAFFEINE ON HUMAN BUCCAL EPITHELIUM CELLS

    Directory of Open Access Journals (Sweden)

    G. B. Skamrova

    2014-04-01

    Full Text Available Now the number of physical and chemical biologically active damage factors dramatically increased. The ways to neutralize such effects have not been studied enough. In this work the techniques of visual assessment of chromatin granulation and of electronegativity of human buccal epithelium cell nuclei were used in order to study the combined effects of the exposure to low-intensity electromagnetic radiation of the millimeter range electromagnetic radiation and to the DNA-binding compounds, such as: antibiotic doxorubicin, mutagens ethidium bromide and proflavine, as well as to caffeine and C60 -fullerene which are not directly interact with DNA. When the action of electromagnetic radiation and DNA-binding compounds is combined, a synergistic effect of reducing the cell response was observed in contrast to the effects caused by electromagnetic radiation and drugs separately. When cells were irradiated in the presence of C60 -fullerene or caffeine, a protective effect of compounds against electromagnetic radiation influence was observed. The obtained results may provide perspectives in the use of the C60 fullerene and caffeine as DNA-protectors under the action of electromagnetic radiation.

  10. Adsorption behavior of 5-fluorouracil on pristine, B-, Si-, and Al-doped C60 fullerenes: A first-principles study

    Science.gov (United States)

    Hazrati, Mehrnoosh Khodam; Hadipour, Nasser L.

    2016-02-01

    Since C60 fullerene has been enormously studied as a drug delivery vehicle, we investigated the interaction between C60 and 5-fluorouracil drug using density functional theory calculations. The electronic and structural properties were explored in terms of binding energies, frontier molecular orbitals, DOS and NBO. To manipulate 5-fluorouracil adsorption properties on the C60, we substituted a carbon atom with boron, silicon and aluminum. In contrast to the pristine C60, the binding energy of 5-fluorouracil to the doped fullerenes is much more negative and the HOMO-LUMO gaps are significantly enlarged. Our results suggest that doping may improve C60 drug delivery properties.

  11. Incorporation of Pure Fullerene into Organoclays : Towards C60-Pillared Clay Structures

    NARCIS (Netherlands)

    Tsoufis, Theodoros; Georgakilas, Vasileios; Ke, Xiaoxing; Van Tendeloo, Gustaaf; Rudolf, Petra; Gournis, Dimitrios

    2013-01-01

    In this work, we demonstrate the successful incorporation of pure fullerene from solution into two-dimensional layered aluminosilicate minerals. Pure fullerenes are insoluble in water and neutral in terms of charge, hence they cannot be introduced into the clay galleries by ion exchange or intercala

  12. Comparative Analysis of the Antineoplastic Activity of C60 Fullerene with 5-Fluorouracil and Pyrrole Derivative In Vivo

    Science.gov (United States)

    Lynchak, O. V.; Prylutskyy, Yu I.; Rybalchenko, V. K.; Kyzyma, O. A.; Soloviov, D.; Kostjukov, V. V.; Evstigneev, M. P.; Ritter, U.; Scharff, P.

    2017-01-01

    The antitumor activity of pristine C60 fullerene aqueous solution (C60FAS) compared to 5-fluorouracil (5-FU) and pyrrole derivative 1-(4-Cl-benzyl)-3-Cl-4-(CF3-fenylamino)-1H-pyrrol-2.5-dione (MI-1) cytostatic drugs was investigated and analyzed in detail using the model of colorectal cancer induced by 1.2-dimethylhydrazine (DMH) in rats. The number, size, and location of the tumors were measured, and the pathology was examined. It was found that the number of tumors and total lesion area decreased significantly under the action of C60FAS and MI-1. Because these drugs have different mechanisms of action, their simultaneous administration can potentially increase the effectiveness and significantly reduce the side effects of antitumor therapy.

  13. Geometric modeling of midi-fullerene growth from C32 to C60

    Directory of Open Access Journals (Sweden)

    Alexander I. Melker

    2017-03-01

    Full Text Available Axonometric projections together with the corresponding graphs for fullerenes are constructed in the range from 32 to 60. The growth of fullerenes is studied on the basis of a mechanism according to which a carbon dimer embeds in a hexagon of an initial fullerene. This leads to stretching and breaking the covalent bonds which are parallel to arising tensile forces. In this case, instead of a hexagon adjoining two pentagons, two adjacent pentagons adjoining two hexagons are obtained. As a result, there arises a new atomic configuration and there is mass increase of two carbon atoms. We considered the direct descendants of fullerene C32; namely, C2n, where n=17–30.

  14. Ortho-para conversion of endohedral water in the fullerene C60 at cryogenic temperatures

    Science.gov (United States)

    Shugai, Anna; Nagel, U.; Rõõm, T.; Mamone, S.; Concistrè, M.; Meier, B.; Krachmalnicoff, A.; Whitby, R. J.; Levitt, M. H.; Lei, Xuegong; Li, Yongjun; Turro, N. J.

    2015-03-01

    Water displays the phenomenon of spin isomerism in which the two proton spins either couple to form a triplet (ortho water, I = 1) or a singlet nuclear spin state (para water, I = 0). Here we study the interconversion of para and ortho water. The exact mechanism of this process is still not fully understood. In order to minimize interactions between molecules we use a sample where a single H2O is trapped in the C60 molecular cage (H2O@C60)andH2O@C60iscrystallized.H2O@C60 has long-lived ortho state and ortho-para conversion kinetics is non-exponential at LHeT. We studied mixtures of H2O@C60, D2O@C60 and C60 using IR absorption, NMR and dielectric measurements. We saw the speeding up of the interconversion with the growth of H2O@C60 concentration in C60 or when D2O@C60 was added. At some temperatures the kinetics is exponential. Models are discussed in order to explain the T and concentration dependence of ortho-para interconversion kinetics. This work was supported by institutional research funding IUT23-3 of the Estonian Ministry of Education and Research.

  15. Molecular solubilization of fullerene C60 in water by γ-cyclodextrin thioethers

    Directory of Open Access Journals (Sweden)

    Hai Ming Wang

    2012-09-01

    Full Text Available Various hydrophilic γ-cyclodextrin (CD thioethers, containing neutral or ionic side arms were found to form molecular disperse solutions of C60 in water reaching concentrations of 15 mg/L. Equilibrium state was approached after seven days without the use of organic cosolvents. The 1:2 stoichiometry of the C60/γ-CD thioether complexes was demonstrated by a parabolic phase-solubility diagram. In contrast, native γ-CD forms nanoparticles with C60. Particle sizes of C60 were determined by dynamic light scattering.

  16. Intraperitoneal Exposure to Nano/Microparticles of Fullerene (C60) Increases Acetylcholinesterase Activity and Lipid Peroxidation in Adult Zebrafish (Danio rerio) Brain

    OpenAIRE

    Gonzalo Ogliari Dal Forno; Luiza Wilges Kist; Mariana Barbieri de Azevedo; Rachel Seemann Fritsch; Talita Carneiro Brandão Pereira; Roberta Socoowski Britto; Sílvia Stanisçuaski Guterres; Irene Clemes Külkamp-Guerreiro; Carla Denise Bonan; José María Monserrat; Maurício Reis Bogo

    2013-01-01

    Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxi...

  17. An investigation on dispersion and stability of water-soluble fullerenol (C60OH) in water via UV-Visible spectroscopy

    Science.gov (United States)

    Najafi, Abolhassan

    2017-02-01

    An investigation on dispersion, stability, and agglomeration of water-soluble fullerenol in water was studied via UV-Vis spectroscopy. The results showed that the dispersion quality and stability of water-soluble fullerenol commenced decreasing after 150 h (more than six days) of solution preparation time. Furthermore, increasing the fullerenol concentration in water (Cfullerenol) showed promotion of the agglomeration in lower residence time. Considering the results of DLS and HRTEM micrographs, an average particle size of the fullerenol in the solution was measured to be ∼150 nm after a residence of 2 months highlighting its high agglomeration tendency even at low concentration.

  18. Fullerene C60 Simulated with a Superconducting Microwave Resonator and Test of the Atiyah-Singer Index Theorem

    Science.gov (United States)

    Dietz, B.; Klaus, T.; Miski-Oglu, M.; Richter, A.; Bischoff, M.; von Smekal, L.; Wambach, J.

    2015-07-01

    We report first experiments with a macroscopic-size superconducting microwave resonator that has the geometric structure of the C60 fullerene molecule. Our high-resolution measurements reveal the exceptional spectral properties that stem from the icosahedral symmetry of its carbon lattice. In particular, they allow us to determine the number of zero-energy modes, i.e., of modes with energy values at the Dirac point existent in the band structure due to the hexagonal arrangements of the carbon atoms, and to test the Atiyah-Singer index theorem which relates this number to the topology of the curved carbon lattice.

  19. From C60 to Infinity: Large-Scale Quantum Chemistry Calculations of the Heats of Formation of Higher Fullerenes.

    Science.gov (United States)

    Chan, Bun; Kawashima, Yukio; Katouda, Michio; Nakajima, Takahito; Hirao, Kimihiko

    2016-02-03

    We have carried out large-scale computational quantum chemistry calculations on the K computer to obtain heats of formation for C60 and some higher fullerenes with the DSD-PBE-PBE/cc-pVQZ double-hybrid density functional theory method. Our best estimated values are 2520.0 ± 20.7 (C60), 2683.4 ± 17.7 (C70), 2862.0 ± 18.5 (C76), 2878.8 ± 13.3 (C78), 2946.4 ± 14.5 (C84), 3067.3 ± 15.4 (C90), 3156.6 ± 16.2 (C96), 3967.7 ± 33.4 (C180), 4364 (C240) and 5415 (C320) kJ mol(-1). In our assessment, we also find that the B3-PW91-D3BJ and BMK-D3(BJ) functionals perform reasonably well. Using the convergence behavior for the calculated per-atom heats of formation, we obtained the formula ΔfH per carbon = 722n(-0.72) + 5.2 kJ mol(-1) (n = the number of carbon atoms), which enables an estimation of ΔfH for higher fullerenes more generally. A slow convergence to the graphene limit is observed, which we attribute to the relatively small proportion of fullerene carbons that are in "low-strain" regions. We further propose that it would take tens, if not hundreds, of thousands of carbons for a fullerene to roughly approach the limit. Such a distinction may be a contributing factor to the discrete properties between the two types of nanomaterials. During the course of our study, we also observe a fairly reliable means for the theoretical calculation of heats of formation for medium-sized fullerenes. This involves the use of isodesmic-type reactions with fullerenes of similar sizes to provide a good balance of the chemistry and to minimize the use of accompanying species.

  20. Orientational order in the stable buckminster fullerene solvate C60·2CBr2H2

    Science.gov (United States)

    Ye, J.; Barrio, M.; Negrier, Ph.; Qureshi, N.; Rietveld, I. B.; Céolin, R.; Tamarit, J. Ll.

    2017-04-01

    Crystals of the solvate C60·2CBr2H2 (monoclinic C2/ m), which is stable in air, were grown by slow evaporation of solutions of C60 in CBr2H2 at room temperature. The high enthalpy change for the complete desolvation process, 54.9 kJ mol-1 of solvent, as well as the relatively large negative excess volume of -49.6 Å3 indicate the presence of strong intermolecular interactions between C60 and CBr2H2. The strong intermolecular interactions are consistent with an overall orientational order for the C60 and the CBr2H2 molecules in the solvate as found by the Rietveld refinement of its crystal structure.

  1. Models and Simulations of C60-Fullerene Plasma Jets for Disruption Mitigation and Magneto-Inertial Fusion

    Science.gov (United States)

    Bogatu, Ioan-Niculae; Galkin, Sergei A.; Kim, Jin-Soo

    2009-11-01

    We present the models and simulation results of C60-fullerene plasma jets proposed to be used for the disruption mitigation on ITER and for magneto-inertial fusion (MIF). The model describing the fast production of a large mass of C60 molecular gas in the pulsed power source by explosive sublimation of C60 micro-grains is detailed. Several aspects of the magnetic ``piston'' model and the 2D interchange (magnetic Rayleigh-Taylor) instability in the rail gun arc dynamics are described. A plasma jet adiabatic expansion model is used to investigate the in-flight three-body recombination during jet transport to the plasma boundary. Our LSP PIC code 3D simulations show that heavy C60 plasmoid penetrates deeply through a transverse magnetic barrier demonstrating self-polarization and magnetic field expulsion effects. The LSP code 3D simulation of two plasma jets head-on injection along a magnetic field lines for MIF are also discussed.

  2. Electrostatic properties of fullerenes under an external electric field: First-principles calculations of energetics for all IPR isomers from C60 to C78

    Science.gov (United States)

    Sorimachi, Jun-ya; Okada, Susumu

    2016-08-01

    Based on first-principles total energy calculations, we analyze the energetics of the fullerene isomers from C60 to C78, all of which satisfy the isolated pentagon rule, under a parallel electric field. Our calculations show that the total energy of the fullerene is proportional to the square of the external electric field. On the other hand, the coefficient of the quadratic energy profile is sensitive to the fullerene species and their orientation. Furthermore, fullerenes possessing lower symmetry exhibit asymmetric quadratic energy profiles with respect to the field, indicating that they possess intrinsic polarization along particular molecular orientations.

  3. Fullerene-C60 derivatives prevent UV-irradiation/ TiO2-induced cytotoxicity on keratinocytes and 3D-skin tissues through antioxidant actions.

    Science.gov (United States)

    Kato, Shinya; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2014-05-01

    Microcorpuscular titanium dioxide (TiO2), a useful sunscreen agent, photocatalyzes generation of reactive oxygen species (ROS). We assessed protective effects of fullerene-C60 derivatives or microcolloidal platinum (Pt) against ultraviolet ray (UV)-irradiation in the presence of TiO2 in vitro. UV-irradiation (8 J/cm2, mixed UVA and UVB) in the presence of 15 ppm TiO2 on HaCaT keratinocytes decreased cell viability as quantified by WST-1 assay, and increased both intracellular ROS and cell-membrane-lipid peroxidation, as quantified by nitroblue-tetrazolium (NBT) assay and diphenyl-1-pyrenylphosphine (DPPP) assay, respectively, whereas all of three phototoxicity-related symptoms were appreciably repressed almost to UV-unirradiational levels by pretreatment with polyvinylpyrrolidone-entrapped fullerene-C60 (C60/PVP) or fullerene-C60 dissolved in squalane (C60/Sqn) in a dose-dependent manner of C60, but scarcely by PVP alone or Sqn alone. In contrast, Pt repressed intracellular ROS generation, but did not prevent either peroxidation of cell-membrane-lipid or cell mortality. Then in the epidermis of 3-dimensional human skin tissue model, UV-irradiation in the presence of TiO2 extensively induced two symptoms such as ROS-generation around perinuclear regions and membrane-lipid peroxidation, both of which were repressed by C60/PVP or C60/Sqn, whereas Pt did not prevent membrane-lipid peroxidation adequately. Thus the advantageous application of the lipophilic antioxidant fullerene-C60 which effectively protects cell membrane against peroxidation. In conclusion, fullerene-C60 can be expected to serve as an antioxidant for scavenging of TiO2-photocatalyzed ROS in the skin surface, and therefore provide a functional improvement of TiO2-containing sunscreens.

  4. Solvent-free functionalization of fullerene C60 and pristine multi-walled carbon nanotubes with aromatic amines

    Science.gov (United States)

    Ramírez-Calera, Itzel J.; Meza-Laguna, Victor; Gromovoy, Taras Yu.; Chávez-Uribe, Ma. Isabel; Basiuk, Vladimir A.; Basiuk, Elena V.

    2015-02-01

    We employed a direct one-step solvent-free covalent functionalization of solid fullerene C60 and pristine multi-walled carbon nanotubes (MWCNTs) with aromatic amines 1-aminopyrene (AP), 2-aminofluorene (AF) and 1,5-diaminonaphthalene (DAN). The reactions were carried out under moderate vacuum, in a wide temperature range of 180-250 °C, during relatively short time of about 2 h. To confirm successful amine attachment, a large number of analytical techniques were used (depending on the nanomaterial functionalized) such as Fourier transform infrared, Raman, X-ray photoelectron, 13C cross-polarization magic angle spinning NMR spectroscopy, thermogravimetric analysis, laser-desorption ionization time-of-flight mass spectrometry, temperature-programmed desorption with mass spectrometric detection, as well as scanning and transmission electron microscopy. The nucleophilic addition of the aromatic amines to C60 molecule was studied theoretically by using density functional theory (PBE GGA functional with Grimme dispersion correction in conjunction with the DNP basis set). In the case of crystalline C60, the solvent-free technique has a limited applicability due to poor diffusion of vaporous aromatic amines into the bulk. Nevertheless, the approach proposed allows for a facile preparation of aromatic amine-functionalized pristine MWCNTs without contamination with other chemical reagents, detergents and solvents, which is especially important for a vast variety of nanotube applications spanning from nanoelectronics to nanomedicine.

  5. Unravelling the multilayer growth of the fullerene C60 in real time

    Science.gov (United States)

    Bommel, S.; Kleppmann, N.; Weber, C.; Spranger, H.; Schäfer, P.; Novak, J.; Roth, S.V.; Schreiber, F.; Klapp, S.H.L.; Kowarik, S.

    2014-01-01

    Molecular semiconductors are increasingly used in devices, but understanding of elementary nanoscopic processes in molecular film growth is in its infancy. Here we use real-time in situ specular and diffuse X-ray scattering in combination with kinetic Monte Carlo simulations to study C60 nucleation and multilayer growth. We determine a self-consistent set of energy parameters describing both intra- and interlayer diffusion processes in C60 growth. This approach yields an effective Ehrlich–Schwoebel barrier of EES=110 meV, diffusion barrier of ED=540 meV and binding energy of EB=130 meV. Analysing the particle-resolved dynamics, we find that the lateral diffusion is similar to colloids, but characterized by an atom-like Schwoebel barrier. Our results contribute to a fundamental understanding of molecular growth processes in a system, which forms an important intermediate case between atoms and colloids. PMID:25369851

  6. Reducing HAuCl4 by the C60 dianion: C60-directed self-assembly of gold nanoparticles into novel fullerene bound gold nanoassemblies

    Science.gov (United States)

    Liu, Wei; Gao, Xiang

    2008-10-01

    The C60 dianion is used to reduce tetrachloroauric acid (HAuCl4) for the first time; three-dimensional C60 bound gold (Au-C60) nanoclusters are obtained from C60-directed self-assembly of gold nanoparticles due to the strong affinities of Au-C60 and C60-C60. The process was monitored in situ by UV-vis-NIR spectroscopy. The resulting Au-C60 nanoclusters were characterized using transmission electron microscopy (TEM), selected area electron diffraction (SAED), energy-dispersive spectroscopy (EDS), x-ray powder diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and FT-IR and Raman spectroscopies. TEM demonstrates the formation of 3D nanonetwork aggregates, which are composed of discrete gold nanocores covered with a C60 monolayer. The SAED and XRD patterns indicate that the gold nanocores inside the capped C60 molecules belong to the face-centred cubic crystal structure, while the C60 molecules are amorphous. The EDS and XPS measurements validate that the Au-C60 nanoclusters contain only Au and C elements and Au3+ is reduced to Au0. FT-IR spectroscopy shows the chemiadsorption of C60 to the gold nanocores, while Raman spectroscopy demonstrates the electron transfer from the gold nanocores to the chemiadsorbed C60 molecules. Au-C60 nanoclusters embedded in tetraoctyl-n-ammonium bromide (TOAB) on glassy carbon electrodes (GCEs) have been fabricated and have shown stable and well-defined electrochemical responses in aqueous solution.

  7. The role of humic acid in stabilizing fullerene (C60) suspensions%腐殖酸对富勒烯C60的悬浮作用

    Institute of Scientific and Technical Information of China (English)

    Lu-qing ZHANG; Yu-kun ZHANG; Xiu-chun LIN; Kun YANG; Dao-hui LIN

    2014-01-01

    Natural organic matter (NOM) has a profound effect on the colloidal stability of discharged C60 nanoparticles in the water environment, which influences the environmental behaviors and risks of C60 and therefore merits more specific studies. This study investigates the effects of humic acid (HA), as a model NOM, on the aqueous stabilization of C60 powder and the colloidal stability of a previously suspended C60 suspension (aqu/nC60) with variations of pH values and ionic strengths. Our results reveal that HA could disperse C60 powder in water to some degree, but was unable to stably suspend them. The aqu/nC60 could remain stable at pH>4 but was destabilized at lower pH values. However, the colloidal stability of aqu/nC60 in the presence of HA was insensitive to pH 3-11, owing to the adsorption of HA onto nC60 and the increased electrosteric repulsions among nC60 aggregates. The colloidal stability of aqu/nC60, with and without HA, decreased as we increased the valence and concentration of the added cations. HA was found to mitigate the destabilization effect of Na+on the colloidal stability of aqu/nC60 by increasing the critical coagulation concentration (CCC) of Na+, while HA lowered the CCCs of Ca2+and La3+probably by the bridging effect of nC60 with HA aggregates formed through the intermolecular bridging of the HA macromolecules via cation complexation at high concentrations of cations with high valences.%研究目的:腐殖酸(HA)对富勒烯(C60)粉末的悬浮作用以及pH、离子强度对HA-C60悬浮性能的影响。  创新要点:研究水质条件对C60悬浮性能的影响。  研究方法:测定C60粉末在HA溶液中的zeta电位,水力学粒径和悬浮浓度;HA存在下,C60悬浮体系的zeta电位与水力学粒径随pH的变化及C60悬浮体系团聚动力学随离子强度的变化。  重要结论:HA对C60粉末起到一定的分散作用,但不能使其长时间稳定悬浮于水中。当pH<4时,C60

  8. Reduced working electrode based on fullerene C60 nanotubes-DNA: Characterization and application

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Xuzhi [Key Laboratory of Eco-Chemical Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, No. 106, Nanjing Road, Qingdao 266071, Shandong (China); Qu Yongtao [Key Laboratory of Rubber-plastics of Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Piao Guangzhe, E-mail: piao@qust.edu.cn [Key Laboratory of Rubber-plastics of Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Zhao Jian [Key Laboratory of Rubber-plastics of Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Jiao Kui, E-mail: Kjiao@qust.edu.cn [Key Laboratory of Eco-Chemical Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China)

    2010-11-25

    Fullerene C{sub 60} nanotubes (FNTs) were functionalized with sequence-specific single-stranded DNA to form a kind of complexes (FNT-DNA), which could be brought efficiently into aqueous solution. The dispersed FNT-DNA could form a layer of stable film on the surface of glassy carbon electrode (GCE). In the Britton-Robinson buffer solution of pH {>=}7.0, the FNT-DNA modified on the GCE presented an irreversible two-step six-electron transfer reduction reaction. The reduced modified electrode had a rather wide electrochemical window and could be used as a functionalized working electrode, which showed a good enrichment capability towards the positively charged molecules. The selective detection of dopamine in the presence of a high amount of ascorbic acid could be realized at the reduced FNT-DNA-modified GCE in neutral buffer solution.

  9. Static and Dynamic Energetic Disorders in the C 60 , PC 61 BM, C 70 , and PC 71 BM Fullerenes

    KAUST Repository

    Tummala, Naga Rajesh

    2015-09-17

    We use a combination of molecular dynamics simulations and density functional theory calculations to investigate the energetic disorder in fullerene systems. We show that the energetic disorder evaluated from an ensemble average contains contributions of both static origin (time-independent, due to loose packing) and dynamic origin (time-dependent, due to electron-vibration interactions). In order to differentiate between these two contributions, we compare the results obtained from an ensemble average approach with those derived from a time average approach. It is found that in both amorphous C60 and C70 bulk systems, the degrees of static and dynamic disorder are comparable, while in the amorphous PC61BM and PC71BM systems, static disorder is about twice as large as dynamic disorder. © 2015 American Chemical Society.

  10. Selective introduction of organic groups to C60 and C70 using organoboron compounds and rhodium catalyst: a new synthetic approach to organo(hydro)fullerenes.

    Science.gov (United States)

    Nambo, Masakazu; Segawa, Yasutomo; Wakamiya, Atsushi; Itami, Kenichiro

    2011-02-01

    A Rh-catalyzed reaction of C(60) and C(70) with organoboron compounds is described. This new catalytic method enables introduction of various organic groups onto C(60) and C(70). [Rh(cod)(MeCN)(2)]BF(4) proved to be the most effective catalyst in terms of productivity and selectivity. The reaction generally proceeds with a high regioselectivity and in a mono-addition selective manner. It was found that water is an essential additive to promote the reaction. By X-ray crystal structure analysis, we have confirmed the reaction site of organometallic-based hydroarylation of C(70) for the first time. Various functional fullerenes, such as fullerene-tagged amino acids and fullerene-capped π systems, can be synthesized. The X-ray crystal structure of biphenyl-attached C(60) revealed an interesting opportunity for the well-organized alignment of bucky balls by taking advantage of CH-π interactions.

  11. Modest vasomotor dysfunction induced by low doses of C60 fullerenes in apolipoprotein E knockout mice with different degree of atherosclerosis

    DEFF Research Database (Denmark)

    Vesterdal, Lise K; Folkmann, Janne K; Jacobsen, Nicklas R

    2009-01-01

    (apoE-/-) with different degree of atherosclerosis. RESULTS: The aged apoE-/-mice had lower endothelium-dependent vasorelaxation elicited by acetylcholine in aorta segments mounted in myographs and the phenylephrine-dependent vasoconstriction response was increased. One hour after an intraperitoneal...... injection of 0.05 or 0.5 mg/kg of C60 fullerenes, the young apoE-/- mice had slightly reduced maximal endothelium-dependent vasorelaxation. A similar tendency was observed in the old apoE-/- mice. Hampered endothelium-independent vasorelaxation was also observed as slightly increased EC50 of sodium...... nitroprusside-induced vasorelaxation response in young apoE-/- mice. CONCLUSION: Treatment with C60 fullerenes affected mainly the response to vasorelaxation in young apoE-/- mice, whereas the vasomotor dysfunction in old apoE-/- mice with more advanced atherosclerosis was less affected by acute C60 fullerene...

  12. Modest vasomotor dysfunction induced by low doses of C60 fullerenes in apolipoprotein E knockout mice with different degree of atherosclerosis

    Directory of Open Access Journals (Sweden)

    Loft Steffen

    2009-02-01

    Full Text Available Abstract Background Exposure to small size particulate matter in urban air is regarded as a risk factor for cardiovascular effects, whereas there is little information about the impact on the cardiovascular system by exposure to pure carbonaceous materials in the nano-size range. C60 fullerenes are nano-sized particles that are expected to have a widespread use, including cosmetics and medicines. Methods We investigated the association between intraperitoneal injection of pristine C60 fullerenes and vasomotor dysfunction in the aorta of 11–13 and 40–42 weeks old apolipoprotein E knockout mice (apoE-/- with different degree of atherosclerosis. Results The aged apoE-/-mice had lower endothelium-dependent vasorelaxation elicited by acetylcholine in aorta segments mounted in myographs and the phenylephrine-dependent vasoconstriction response was increased. One hour after an intraperitoneal injection of 0.05 or 0.5 mg/kg of C60 fullerenes, the young apoE-/- mice had slightly reduced maximal endothelium-dependent vasorelaxation. A similar tendency was observed in the old apoE-/- mice. Hampered endothelium-independent vasorelaxation was also observed as slightly increased EC50 of sodium nitroprusside-induced vasorelaxation response in young apoE-/- mice. Conclusion Treatment with C60 fullerenes affected mainly the response to vasorelaxation in young apoE-/- mice, whereas the vasomotor dysfunction in old apoE-/- mice with more advanced atherosclerosis was less affected by acute C60 fullerene treatment. These findings represent an important step in the hazard characterization of C60 fullerenes by showing that intraperitoneal administration is associated with a moderate decrease in the vascular function of mice with atherosclerosis.

  13. Adsorption and self-assembly of fullerenes on Si(111)√{ 3 } ×√{ 3 }-Ag: C60 versus C70

    Science.gov (United States)

    Olyanich, D. A.; Mararov, V. V.; Utas, T. V.; Zotov, A. V.; Saranin, A. A.

    2016-11-01

    Behavior of C60 and C70 fullerenes adsorbed onto Si(111)√{ 3 } ×√{ 3 }-Ag is compared on the basis of STM observations. Such characteristics as sticking coefficient, migration rate, attachment/detachment rate from the molecular islands are considered. Room-temperature sticking coefficient for C70 is slightly greater than that for C60. Due to their non-spherical shape, C70 are less mobile than spherical C60. For both types of fullerenes, mobility of molecules on the fullerene layer is significantly retarded as compared to that on bare Si(111)√{ 3 } ×√{ 3 }-Ag surface. Self-assembly of C60 obeys layer-by-layer growth mode, while C70 follows multi-layer mode, a sign of a greater Ehrlich-Schwoebel barrier. Alternating deposition of C60 and C70 paves the way to fabricate planar C60/C70 heterostructures with the most promising results being obtained with nanostructured islands grown on C60 monomolecular layer.

  14. Radiosensitization by fullerene-C60 dissolved in squalene on human malignant melanoma through lipid peroxidation and enhanced mitochondrial membrane potential

    Science.gov (United States)

    Kato, Shinya; Kimura, Masatsugu; Miwa, Nobuhiko

    2014-04-01

    We examined fullerene-C60 dissolved in squalene (C60/Sqe) for the ability to potentiate the radiosensitization under X-ray irradiation on human malignant melanoma HMV-II cells, which were treated with C60/Sqe and thereafter irradiated with X-ray. The cell proliferation for C60/Sqe was inhibited more markedly than for Sqe alone. Meanwhile, cell proliferation was almost unaltered for C60/squalane (Sqa) or Sqa, a hydrogenated form of Sqe, as compared to no-additive control. Thus radiosensitization of C60/Sqe is attributed to peroxidation of unsaturated bonds of squalene by X-ray-excited C60 in contrast to squalane. The fluorescence images of HMV-II cells stained with Rhodamine123, an indicator for mitochondrial membrane potential, were monitored for 6 h after X-ray irradiation. C60/Sqe obviously exhibited more augmented fluorescence intensity on perinuclear region of HMV-II cells than Sqe alone. TBARS assay showed that the lipid peroxidation level as malondialdehyde-equivalent increased by combination of C60/Sqe and X-ray dose-dependently on X-ray doses. C60/Sqe exhibited lipid peroxidation more markedly by 1.2-fold than Sqe alone. Thus the level of lipid peroxidation of squalene was sufficiently higher in C60/Sqe than in Sqe in the absence of C60 under X-ray irradiation, suggesting the combination of C60/Sqe and X-ray irradiation induced radiosensitization on HMV-II cells by peroxidation of absorbed Sqe in mitochondrial membrane via oxidative stress mediated by fullerene-C60.

  15. In silico properties characterization of water-soluble γ-cyclodextrin bi-capped C60 complex: free energy and geometrical insights for stability and solubility.

    Science.gov (United States)

    Cao, Ruyin; Wu, Shanshan

    2015-06-25

    Cyclodextrin-related host-guest encapsulation is pivotal to modulate the solubility of C60, thereby promoting its potential therapeutic applications. Here we present a computational study on γ-cyclodextrin bi-capped C60 complex, probing characteristics for all the possible stoichiometry in aqueous solution. The potential of mean force (PMF) delineating the association process was computed, while the geometrical features of corresponding thermodynamically-favored stoichiometry are captured by molecular dynamics simulations, which provides insightful explanations to previous experimental and computational results. PMF partitioning indicates that intermolecular van der Waals dispersion forces are essential for molecular recognition and self-assembly, and the hydrogen-bonding interactions play a key role in dissolving the complex in water.

  16. Photophysical Properties and Photoinduced Electron Transfer between [60]Fullerene-Containing Cyclic Sulphoxide [ C60-C6H8SO] and Tetrathiafulvalene (TTF) by Laser Flash Photolysis

    Institute of Scientific and Technical Information of China (English)

    ZENG,He-Ping(曾和平)

    2002-01-01

    Photoinduced electron transfer (PET) processes between C60-C6H8SO and Tetrathiafulvalene (TTF) have been studied by nanosecond laser photolysis. Quantum yields (φet) and rate constants of electron transfer (ket) from TTF to excited triplet state of [ 60 ] fullerene-containing cyclic sulphoxide in benzonitrile (BN) have been evaluated by observing the transient absorption bands in the NIR region. With the decay of excited triplet state of [ 60 ] fullerene-containing cyclic sulphoxide, the rise of radical anion of [60]fullerene-containing cyclic sulphoxide is observed.

  17. Distribution and Biomarker of Carbon-14 Labeled Fullerene C60 ([14C(U)]C60) in Pregnant and Lactating Rats and their Offspring after Maternal Intravenous Exposure

    Science.gov (United States)

    Snyder, Rodney W.; Fennell, Timothy R.; Wingard, Christopher J.; Mortensen, Ninell P.; Holland, Nathan A.; Shannahan, Jonathan H.; Pathmasiri, Wimal; Lewin, Anita H.; Sumner, Susan C. J.

    2015-01-01

    A comprehensive distribution study was conducted in pregnant and lactating rats exposed to a suspension of uniformly carbon-14 labeled C60 ([14C(U)]C60). Rats were administered [14C(U)]C60 (~0.2 mg [14C(U)]C60/kg body weight) or 5% polyvinylpyrrolidone (PVP)-saline vehicle via a single tail vein injection. Pregnant rats were injected on gestation day (GD) 11 (terminated with fetuses after either 24h or 8d), GD15 (terminated after 24h or 4d), or GD18 (terminated after 24h). Lactating rats were injected on postnatal day 8 and terminated after 24h, 3d or 11d. The distribution of radioactivity in pregnant dams was influenced by both the state of pregnancy and time of termination after exposure. The percentage of recovered radioactivity in pregnant and lactating rats was highest in liver and lungs. Radioactivity was quantitated in over 20 tissues. Radioactivity was found in placenta and in fetuses of pregnant dams, and in the milk of lactating rats and in pups. Elimination of radioactivity was <2% in urine and feces at each time point. Radioactivity remained in blood circulation up to 11 days after [14C(U)]C60 exposure. Biomarkers of inflammation, cardiovascular injury and oxidative stress were measured to study the biological impacts of [14C(U)]C60 exposure. Oxidative stress were elevated in female pups of exposed dams. Metabolomics analysis of urine showed that [14C(U)]C60 exposure to pregnant rats impacted the pathways of vitamin B, regulation of lipid and sugar metabolism and aminoacyl-tRNA biosynthesis. This study demonstrated that [14C(U)]C60 crosses the placenta at all stages of pregnancy examined, and is transferred to pups via milk. PMID:26081520

  18. Effect of heating of the electronic subsystem on the thermal stability of the C-60 and C-20 fullerenes and (C-20)(2) cluster molecule

    NARCIS (Netherlands)

    Davydov, I. V.

    2007-01-01

    The effect of heating of the electronic subsystem on the thermal stability of C-60 and C-20 fullerenes and a (C-20)(2) cluster molecule is investigated theoretically. It is demonstrated that the excitation of electrons to upper energy levels in accordance with the Fermi-Dirac distribution function d

  19. Effects of stable aqueous fullerene nanocrystal (nC60) on Daphnia magna:Evaluation of hop frequency and accumulations under different conditions

    Institute of Scientific and Technical Information of China (English)

    Xianji Tao; Yiliang He; Bo Zhang; Yongsheng Chen; Joseph B. Hughes

    2011-01-01

    We investigated the effects of environmental factors and properties of water-stable crystal fullerene (nC60) on the uptake of nC60 by Daphnia magna based on known accumulation in our laboratory. This study was performed for seven days using different environmental factors including temperature, pH, water hardness, concentration (density of particle), and particle size. Results demonstrated that body burden of C60 increased with time in all experiments. Body burden of C60 increased with increasing concentration and particle size, and uptake of particles >100 nm reached their maximums more quickly than those <100 nm. Under high hardness in aqueous systems with lower pH and high temperature, uptake was higher than those under opposite conditions. Uptake in all batch tests reached balance within five days. Both nC60 properties and environmental factors influenced uptake of nC60 by D.magna in an aqueous system. Additionally, environmental factors may have affected accumulation by changing nC60 properties, which are critical to understand the accumulation of fullerenes in aqueous systems.

  20. Modeling adsorption of brominated, chlorinated and mixed bromo/chloro-dibenzo-p-dioxins on C60 fullerene using Nano-QSPR

    Directory of Open Access Journals (Sweden)

    Piotr Urbaszek

    2017-03-01

    Full Text Available Many technological implementations in the field of nanotechnology have involved carbon nanomaterials, including fullerenes such as the buckminsterfullerene, C60. The unprecedented properties of such organic nanomaterials (in particular their large surface area gained extensive attention for their potential use as organic pollutant sorbents. Sorption interactions can be very hazardous and useful at the same time. This work investigates the influence of halogenation by bromine and/or chlorine in dibenzo-p-dioxins on their sorption ability on the C60 fullerene surface. Halogenated dibenzo-p-dioxins (PXDDs, where X = Br or Cl are ever-present in the environment and accidently produced in many technological processes in only approximately known quantities. If all combinatorial Br and/or Cl dioxin substitution possibilities are present in the environment, the experimental characterization and investigation of sorbent effectiveness is more than difficult. In this work, we have developed a quantitative structure–property relationship (QSPR model (R2 = 0.998, predicting the adsorption energy [kcal/mol] for 1,701 PXDDs adsorbed on C60 (PXDD@C60. Based on the QSPR model reported herein, we concluded that the lowest energy PXDD@C60 complexes are those that the World Health Organization (WHO considers to be less dangerous with respect to the aryl hydrocarbon receptor (AhR toxicity mechanism. Therefore, the effectiveness of fullerenes as sorbent agents may be underestimated as sorption could be less effective for toxic congeners than previously believed.

  1. Ultrafast energy redistribution in C(60) fullerenes: a real time study by two-color femtosecond spectroscopy.

    Science.gov (United States)

    Shchatsinin, Ihar; Laarmann, Tim; Zhavoronkov, Nick; Schulz, Claus Peter; Hertel, Ingolf V

    2008-11-28

    Strong-field excitation and energy redistribution dynamics of C(60) fullerenes are studied by means of time-resolved mass spectrometry in a two-color femtosecond pump-probe setup. Resonant pre-excitation of the electronic system via the first dipole-allowed HOMO-->LUMO+1(t(1g)) (HOMO denotes highest occupied molecular orbital and LUMO denotes lowest unoccupied molecular orbital) transition with ultrashort 25 fs pulses at 399 nm of some 10(12) W cm(-2) results in a highly nonequilibrium distribution of excited electrons and vibrational modes in the neutral species. The subsequent coupling among the electronic and nuclear degrees of freedom is monitored by probing the system with time-delayed 27 fs pulses at 797 nm of some 10(13) W cm(-2). Direct information on the characteristic relaxation time is derived from the analysis of transient singly and multiply charged parent and fragment ion signals as a function of pump-probe delay and laser pulse intensity. The observed relaxation times tau(el) approximately 60-400 fs are attributed to different microcanonical ensembles prepared in the pre-excitation process and correspond to different total energy contents and energy sharing between electronic and vibrational degrees. The characteristic differences and trends allow one to extract a consistent picture for the formation dynamics of ions in different charge states and their fullerenelike fragments and give evidence to collective effects in multiple ionization such as plasmon-enhanced energy deposition.

  2. Electronic structure, stability and non-linear optical properties of aza-fullerenes C60-2nN2n(n=1–12

    Directory of Open Access Journals (Sweden)

    K. Srinivasu

    2012-12-01

    Full Text Available Through ab initio based density functional theory calculations, we have investigated the electronic structure, stability and non-linear optical properties of a series of nitrogen substituted fullerenes (azafullerenes with the general formula C60-2nN2n (n=1–12. For each system, we have considered different possible isomers and the minimum energy isomer is subjected to further detailed investigations. We have calculated different properties such as HOMO-LUMO gaps, vertical ionization potentials, vertical electron affinities, etc. to verify the stability of the considered fullerenes. From the Hessian calculations, it is observed that all the fullerenes are not only associated with real vibrational frequencies, but the minimum frequencies are also found to be considerably large which further confirms the stability of the considered fullerenes. We find that the presence of unperturbed C6 rings enhances the stability of the fullerene whereas, the -N-C-N- fragments are found to destabilize the structure. At lower doping concentration, the stabilization due to C6 is more predominant and as the doping concentration is increased, the destabilization due to nitrogen-nitrogen repulsion plays a more important role. Our calculated polarizability and hyperpolarizability parameters of C60 are found to be in good agreement with the earlier reported results. On nitrogen doping, considerable variation is observed in the non-linear optical coefficients, which can be helpful in designing new photonic devices.

  3. Transient Absorption Spectral Characterization of Electron Transfer between Fullerenes (C60/C70) and N, N, N', N' -Tetra(p-methylphenyl)-4,4'-diamino-1, 1'-diphenyl Sulphide (TPDAS)

    Institute of Scientific and Technical Information of China (English)

    ZENG,He-Ping(曾和平)

    2002-01-01

    In search of new systems with a photoexcited redox pair which exhibits a strong and stable photoinduced absorption band to understand the photophyscial and photochemical properties of electron transfer between fullerenes (C60/C70) and organic donor [N, N, N', N'-tetra(p-methylphenyl)-4,4'-diamino-1,1'-diphenyl sulphide(TP DAs) ], we studied characteristic absorption spectra in the near-IR region obtained from 532 nm nanosecond laser flash photolysis of a mixture of the fullerenes (C60/C70) and TPDAS in polar solvents. When fullerenes (C60/C70) were photoexcited, the rise of the radical anion of fullerenes (C60/C70) with the rapid decay of their excited triplet states were observed in benzonitrile. It can be deduced that the electron transfer reaction does take place from TPDAS to excited triplet state of fullerenes (C60/C70). The rate conalso evaluated.

  4. Raman study of the photopolymer formation in the {Pt(dbdtc)2}·C60 fullerene complex and the decomposition kinetics of the photo-oligomers

    Science.gov (United States)

    Meletov, K. P.; Velkos, G.; Arvanitidis, J.; Christofilos, D.; Kourouklis, G. A.

    2017-08-01

    The photopolymer formation in the fullerene layers of the C60 complex with platinum dibenzyldithiocarbamate is reported for the first time. The photo-oligomer peaks appear in the Raman spectra near the Ag(2) mode of the C60 molecule upon sample illumination with various laser wavelengths. The photo-oligomers are unstable upon heating and revert back to the C60 monomeric state. The activation energy of the thermal decomposition, obtained from the Arrhenius dependence of the decay time constant on temperature, is (1.12 ± 0.11) eV and the photo-oligomers decompose at ∼130 °C, being more fragile than the crystalline polymers of C60.

  5. Preparation of highly stable fullerene C60 decorated graphene oxide nanocomposite and its sensitive electrochemical detection of dopamine in rat brain and pharmaceutical samples.

    Science.gov (United States)

    Thirumalraj, Balamurugan; Palanisamy, Selvakumar; Chen, Shen-Ming; Lou, Bih-Show

    2016-01-15

    The research community has continuously paid much attention on the preparation of hybrid of carbon nanomaterials owing to combine their unique properties. Herein, we report the preparation of highly stable fullerene C60 (C60) wrapped graphene oxide (GO) nanocomposite by using a simple sonication method. The fabricated GO-C60 nanocomposite modified glassy carbon electrode shows a good sensitivity and lower oxidation overpotential towards dopamine (DA) than that of pristine GO and C60. The fabricated sensor detects the DA in the linear response range of 0.02-73.5μM. The limit of detection is estimated to be 0.008μM based on 3σ with a sensitivity of 4.23μAμM(-1)cm(-2). The fabricated sensor also exhibits other features such as good selectivity, stability, reproducibility and repeatability. The proposed sensor exhibits good practicality towards the detection of DA in rat brain and commercial DA injection samples.

  6. Strategies for quantifying C60 fullerenes in environmental and biological samples and implications for studies in environmental health and ecotoxicology

    OpenAIRE

    Pycke, Benny F. G.; Benn, Troy M.; Herckes, Pierre; Westerhoff, Paul; Halden, Rolf U.

    2011-01-01

    Fullerenes are sphere-like molecules with unique physico-chemical properties, which render them of particular interest in biomedical research, consumer products and industrial applications. Human and environmental exposure to fullerenes is not a new phenomenon, due to a long history of hydrocarbon-combustion sources, and will only increase in the future, as incorporation of fullerenes into consumer products becomes more widespread for use as anti-aging, anti-bacterial or anti-apoptotic agents.

  7. Immunotoxicity of nanoparticles: a computational study suggests that CNTs and C60 fullerenes might be recognized as pathogens by Toll-like receptors

    Science.gov (United States)

    Turabekova, M.; Rasulev, B.; Theodore, M.; Jackman, J.; Leszczynska, D.; Leszczynski, J.

    2014-03-01

    Over the last decade, a great deal of attention has been devoted to study the inflammatory response upon exposure to multi/single-walled carbon nanotubes (CNTs) and different fullerene derivatives. In particular, carbon nanoparticles are reported to provoke substantial inflammation in alveolar and bronchial epithelial cells, epidermal keratinocytes, cultured monocyte-macrophage cells, etc. We suggest a hypothetical model providing the potential mechanistic explanation for immune and inflammatory responses observed upon exposure to carbon nanoparticles. Specifically, we performed a theoretical study to analyze CNT and C60 fullerene interactions with the available X-ray structures of Toll-like receptors (TLRs) homo- and hetero-dimer extracellular domains. This assumption was based on the fact that similar to the known TLR ligands both CNTs and fullerenes induce, in cells, the secretion of certain inflammatory protein mediators, such as interleukins and chemokines. These proteins are observed within inflammation downstream processes resulted from the ligand molecule dependent inhibition or activation of TLR-induced signal transduction. Our computational studies have shown that the internal hydrophobic pockets of some TLRs might be capable of binding small-sized carbon nanostructures (5,5 armchair SWCNTs containing 11 carbon atom layers and C60 fullerene). High binding scores and minor structural alterations induced in TLR ectodomains upon binding C60 and CNTs further supported our hypothesis. Additionally, the proposed hypothesis is strengthened by the indirect experimental findings indicating that CNTs and fullerenes induce an excessive expression of specific cytokines and chemokines (i.e. IL-8 and MCP1).Over the last decade, a great deal of attention has been devoted to study the inflammatory response upon exposure to multi/single-walled carbon nanotubes (CNTs) and different fullerene derivatives. In particular, carbon nanoparticles are reported to provoke

  8. Intraperitoneal Exposure to Nano/Microparticles of Fullerene (C60 Increases Acetylcholinesterase Activity and Lipid Peroxidation in Adult Zebrafish (Danio rerio Brain

    Directory of Open Access Journals (Sweden)

    Gonzalo Ogliari Dal Forno

    2013-01-01

    Full Text Available Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C60 nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis nor to the direct action of nonphotoexcited C60 nano/microparticles on the protein (in vitro results but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60 exposure.

  9. Intraperitoneal Exposure to Nano/Microparticles of Fullerene (C60) Increases Acetylcholinesterase Activity and Lipid Peroxidation in Adult Zebrafish (Danio rerio) Brain

    Science.gov (United States)

    Dal Forno, Gonzalo Ogliari; Kist, Luiza Wilges; de Azevedo, Mariana Barbieri; Fritsch, Rachel Seemann; Pereira, Talita Carneiro Brandão; Britto, Roberta Socoowski; Guterres, Sílvia Stanisçuaski; Külkamp-Guerreiro, Irene Clemes; Bonan, Carla Denise; Monserrat, José María; Bogo, Maurício Reis

    2013-01-01

    Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg) altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C60 nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays) in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis) nor to the direct action of nonphotoexcited C60 nano/microparticles on the protein (in vitro results) but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60 exposure. PMID:23865059

  10. Fullerene-Based Macro-Heterocycle Prepared through Selective Incorporation of Three N and Two O Atoms into C60.

    Science.gov (United States)

    Li, Yanbang; Zhang, Gaihong; Wang, Dian; Xu, Beidi; Xu, Dan; Lou, Ning; Gan, Liangbing

    2016-11-14

    A 14-membered heterocycle is created on the C60 cage skeleton through a multistep procedure. Key steps involve repeated PCl5 -induced hydroxylamino N-O bond cleavage leading to insertion of nitrogen atoms, and also piperidine-induced peroxo O-O bond cleavage leading to insertion of oxygen atoms. The hetero atoms form one pyrrole, two pyran, and one diazepine rings in conjunction with the C60 skeleton carbon atoms. The fullerene-based macrocycle showed unique reactivities towards fluoride ion and copper salts. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The study of applicability of dithiocarbamate-coated fullerene C 60 for preconcentration of palladium for graphite furnace atomic absorption spectrometric determination in environmental samples

    Science.gov (United States)

    Leśniewska, Barbara A.; Godlewska, Iwona; Godlewska—Żyłkiewicz, Beata

    2005-03-01

    The present method comprises an off-line enrichment of Pd on the fullerene, C 60, coated with ammonium pyrrolidinedithiocarbamate (APDC), followed by the elution of formed Pd-chelate with ethanol and the subsequent determination of Pd from the eluate by graphite furnace atomic absorption spectrometry. By using fullerene loaded with 0.1% APDC, the analytical system is simplified as the sample can be directly preconcentrated on the column. The following parameters affecting the preconcentration of Pd on C 60 were optimized: amount of ligand used for the coating of fullerene, sample pH, kind of eluent, sample and eluent flow rates, volume and number of fractions of eluent used. The sorption efficiency for Pd on coated fullerene was 99.2±1.1%. The best elution efficiency for Pd from the column was obtained with 0.6 ml of ethanol at a flow rate of 0.2 ml min -1. The limit of detection was 0.044 ng ml -1. The effect of sample pretreatment procedure on the preconcentration of Pd by evaluated method is discussed. The content of Pd in road dust (179.2±17.4 ng g -1) determined by proposed method was in agreement with the results obtained with a reference method. The low recovery of analyte (64%) was obtained for geological material CRM SARM-7 (platinum ore) due to the much higher concentration of interfering elements.

  12. Phenothiazine-bridged cyclic porphyrin dimers as high-affinity hosts for fullerenes and linear array of C60 in self-assembled porphyrin nanotube.

    Science.gov (United States)

    Sakaguchi, Ken-ichi; Kamimura, Takuya; Uno, Hidemitsu; Mori, Shigeki; Ozako, Shuwa; Nobukuni, Hirofumi; Ishida, Masatoshi; Tani, Fumito

    2014-04-01

    Free-bases and a nickel(II) complex of phenothiazine-bridged cyclic porphyrin dimers bearing self-assembling 4-pyridyl groups (M2-Ptz-CPDPy(OCn); M = H2 or Ni, OCn = OC6 or OC3) at opposite meso-positions have been prepared as host molecules for fullerenes. The free-base dimer (H4-Ptz-CPDPy(OC6)) includes fullerenes with remarkably high association constants such as 3.9 ± 0.7 × 10(6) M(-1) for C60 and 7.4 ± 0.8 × 10(7) M(-1) for C70 in toluene. This C60 affinity is the highest value ever among reported receptors composed of free-base porphyrins. The nickel dimer (Ni2-Ptz-CPDPy(OC6)) also shows high affinities for C60 (1.3 ± 0.2 × 10(6) M(-1)) and C70 (over 10(7) M(-1)). In the crystal structure of the inclusion complex of C60 within H4-Ptz-CPDpy(OC3), the C60 molecule is located just above the centers of the porphyrins. The two porphyrin planes are almost parallel to each other and the center-to-center distance (12.454 Å) is close to the optimal separation (∼12.5 Å) for C60 inclusion. The cyclic porphyrin dimer forms a nanotube through its self-assembly induced by C-H···N hydrogen bonds between porphyrin β-CH groups and pyridyl nitrogens as well as π-π interactions of the pyridyl groups. The C60 molecules are linearly arranged in the inner channel of this nanotube.

  13. Fullerene C60-perylene-3,4:9,10-bis(dicarboximide) light-harvesting dyads: Spacer-length and bay-substituent effects on intramolecular singlet and triplet energy transfer

    NARCIS (Netherlands)

    Baffreau, J.; Leroy-Lhez, S.; Nguyên, V.A.; Williams, R.M.; Hudhomme, P.

    2008-01-01

    Novel covalent fullerene C-60-perylene-3,4:9,10-bis(dicarboximide) (C-60-PDI) dyads (1-4) were synthesized and characterized. Their electrochemical and photophysical properties were investigated. Electrochemical studies show that the reduction potential of PDI can be tuned relative to C-60 by molecu

  14. Genotoxicity, cytotoxicity, and reactive oxygen species induced by single-walled carbon nanotubes and C(60) fullerenes in the FE1-Mutatrade markMouse lung epithelial cells

    DEFF Research Database (Denmark)

    Jacobsen, Nicklas Raun; Pojana, Giulio; White, Paul;

    2008-01-01

    Viability, cell cycle effects, genotoxicity, reactive oxygen species production, and mutagenicity of C(60) fullerenes (C(60)) and single-walled carbon nanotubes (SWCNT) were assessed in the FE1-Mutatrade markMouse lung epithelial cell line. None of these particles induced cell death within 24 hr...... at doses between 0 and 200 microg/ml or during long-term subculture exposure (576 hr) at 100 microg/ml, as determined by two different assays. However, cell proliferation was slower with SWCNT exposure and a larger fraction of the cells were in the G1 phase. Exposure to carbon black resulted...... by the comet assay. The mutant frequency in the cII gene was unaffected by 576 hr of exposure to either 100 microg/ml C(60) or SWCNT when compared with control incubations, whereas we have previously reported that carbon black and diesel exhaust particles induce mutations using an identical exposure scenario...

  15. 重结晶-柱色谱联用法分离C60研究%Efficient separation of fullerene C60 with the recrystallization-column chromatography method

    Institute of Scientific and Technical Information of China (English)

    刘慧敏; 彭汝芳; 金波; 楚士晋

    2011-01-01

    The paper is aimed at introducing the recrystallization-column chromatography method to the heightening of the performance of the purification between C60 and C70. We have done a series of efforts trying to separate C60 from the crude fuilerenes by means of recrystal-lization-column chromatography combined technique in our study. In proceeding with our research, the crude fuilerenes soot extract samples were first of all put into a Stoppard Erienmeyer flask with pure oxylene and then heat the whole solution to 80 ℃, while maintaining the state for four hours. Keep stirring the solution electromagnetically in the heating process, the deposit would be filtrated from the supernatant quickly with the solution kept warm. The obtained C60, could be enriched in the solid deposit by centrifugation and then sent for its purification of fuilerenes to be tested by HPLC. The purity of the said C60 obtained as a result of the sedimentation can be made to reach 90% . And, then, it is possible to let the resulted highly purified C60 be treated by column chromatography, which can then use activated carbon as a single stationary phase and toluene as the mobile phase. Under the given condition, the C60 was made dissolved with the toluene under ultrasound again. The solution gained in this case could be let to pass through the column quickly with the final purple fraction collected and concentrated by evaporation. Thus, the pure C60 can be finally obtained. The experimental results from our research indicate that high purity and total recovery with the application of this method proves to be closely related with the mass of activated carbon and the dimension of the column. When the activated carbon and fullerene mass ratio reached a ration of 9:1 with the ratio of height to diameter of the column up to 10:1, it would be possible to increase the final purity of C60 to 99.9% while the total recovering rate could reach 81 % . Compared with the simple recrystallization or column

  16. The effect of squalane-dissolved fullerene-C60 on adipogenesis-accompanied oxidative stress and macrophage activation in a preadipocyte-monocyte co-culture system.

    Science.gov (United States)

    Xiao, Li; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2010-08-01

    Effects of squalane-dissolved fullerene-C60 (Sql-fullerene) on macrophage activation and adipose conversion with oxidative stress were studied using an inflammatory adipose-tissue equivalent (ATE) and OP9 mouse stromal preadipocyte-U937 lymphoma cell co-culture systems. Differentiation of OP9 cells was initiated by insulin-rich serum replacement (SR) as an adipogenic stimulant, and then followed by accumulation of intracellular lipid droplets and reactive oxygen species (ROS), both of which were significantly inhibited by Sql-fullerene. In the OP9-U937 cell co-culture system, U937 cells rapidly differentiated to macrophage-like cells during SR-induced adipogenesis in OP9 cells. The ROS accumulation was in the co-culture more marked than in OP9 cells alone, suggesting that the interaction between adipocytes and monocytes/macrophages promotes inflammatory responses. Sql-fullerene significantly inhibited macrophage activation and low-grade adipogenesis in the OP9-U937 co-culture system. We developed a three-dimensional inflammatory adipose-tissue model "ATE" consisting of, characteristically, U937 cells in the culture-wells, and, in addition, mounted a culture insert containing OP9 cells-populated collagen gel. ATE is enabled with suitable stimulation to represent the pathology of inflammatory disorders, such as macrophage infiltration in adipose tissue. Five-day culturing of ATE in SR medium occurred U937 macrophage migration and intracellular oil-droplet accumulation that were significantly inhibited by Sql-fullerene. Our results suggest that Sql-fullerene might be explored as a potential medicine for the treatment of metabolic syndrome or other obesity-related disorders.

  17. Fullerene antiferromagnetic reconstructed spinterface subsurface layer dominates multi-orbitals spin-splitting and large magnetic moment in C60

    CERN Document Server

    Shao, Yangfan; Pan, Hui; Shi, Xingqiang

    2016-01-01

    The interfaces between organic molecules and metal surfaces with layered antiferromagnetic order have gained increasing interests in the field of antiferromagnetic spintronics. The C60 layered AFM spinterfaces have been studied for C60 bonded only to the outermost ferromagnetic layer. Using density functional theory calculations, here we demonstrate that C60 adsorption can reconstruct the layered AFM Cr(001) surface so that C60 bonds to the top two Cr layers with opposite spin direction. Surface reconstruction drastically changes C60 s spintronic properties 1 the spin-split p-d hybridization involve multi-orbitals of C60 and metal double layers, 2 the subsurface layer dominates the C60 spin properties, and 3) reconstruction induces a large magnetic moment in C60 of 0.58 B, which is a synergetic effect of the top two layers as a result of a magnetic direct-exchange interaction. Understanding these complex spinterfaces phenomena is a crucial step for their device applications. The surface reconstruction can be ...

  18. Thermodynamics of association of water soluble fullerene derivatives [C ₆₀ (OH)n, n = 0, 2, 4, 8 and 12] in aqueous media

    Indian Academy of Sciences (India)

    SONANKI KESHRI; B L TEMBE

    2017-09-01

    The thermodynamics of association of fullerene [C₆₀] and water-soluble fullerene derivatives, i.e., fullerols [C ₆₀ (OH)n, n = 0, 2, 4, 8 and 12] in aqueous solutions have been studied using molecular dynamics simulations. The potentials of mean force (PMFs) bring out the tendency of aggregation of these nanostructuresin water. The extent of hydroxylation seems to have a minor effect on the depth of the contact minima (the first minimum in the PMFs). The positions of the subsequent minima and maxima in the PMFs change with the size of the solute molecules. Higher stability of the contact state of highly hydroxylated fullerols is due to the van der Waals interactions whereas intermolecular solute-solvent hydrogen bonding nearly flattens the PMFs beyond the 2nd minima for higher fullerols. The solvent contributions to the PMFs for all the solute particles studied here are positive. Entropic and enthalpic contributions to the association of solute molecules are calculated in the isothermal-isobaric (NPT) ensemble. We find that the contact pair formation is governed by entropy with the enthalpic contributions being highly unfavorable, whereas the solvent assisted and solvent separated configurations show entropy-enthalpy compensation.

  19. Quantification of fullerene aggregate nC60 in wastewater by high-performance liquid chromatography with UV-vis spectroscopic and mass spectrometric detection.

    Science.gov (United States)

    Wang, Chao; Shang, Chii; Westerhoff, Paul

    2010-06-01

    This paper evaluates the performance of liquid-liquid extraction (LLE) and solid phase extraction (SPE) in separating and concentrating aqueous fullerene (nC(60)) from wastewater and compares UV-vis spectroscopy and mass spectrometry for the quantification of C(60). LLE was suitable for multiple wastewater matrices, while SPE required filtration or reclaimed wastewater and secondary effluent of less suspended solids. Calibration curves plotted as peak areas of UV absorbance at 332 nm against spiked nC(60) concentrations showed good linearity over a range of 20-200 microg L(-1) after 10-fold concentration by LLE, but only over the range of 0.8-2 microg L(-1) for reclaimed wastewater and 0.8-4 microg L(-1) for secondary effluent after 1000-fold concentration by SPE. Recoveries of nC(60) by LLE were in the range of 89-94% with a standard deviation (SD) not more than 2% and recoveries of nC(60) by SPE were much lower, only 18% for reclaimed wastewater and 9% for secondary effluent. The method detection limits (MDLs) of LLE with UV-vis spectroscopy were 3-4 microg L(-1) for six water matrices and the MDLs of SPE with UV-vis spectroscopy were 0.42 microg L(-1) for reclaimed wastewater and 0.64 microg L(-1) for secondary effluent. UV-vis spectroscopy and mass spectrometry gave similar sensitivity. With LLE, mass spectrometry offered a small linear range of 20-60 microg L(-1), but it provided specificity based on the mass-to-charge ratios (m/z) of the molecular ions. This paper demonstrates the feasibility of the combination of different extraction and detection methods to quantify nC(60) in engineered wastewater matrices. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Rotations and vibrations of water molecule inside the fullerene cage: infrared study of H2O@C60

    Science.gov (United States)

    Room, Toomas; Shugai, A.; Nagel, U.; Mamone, S.; Krachmalnicoff, A.; Whitby, R. J.; Levitt, M. H.; Nishida, T.; Murata, Y.; Lei, Xuegong; Li, Yongjun; Turro, N. J.

    2015-03-01

    Water is the second molecule after hydrogen what has been trapped inside the cage of a C60 molecule by the molucular surgery method. We studied isolated water molecule isotopologs H2O, D2O, and HDO in the solid phase at cryogenic temperatures using IR spectroscopy. The water molecule rotation transitions were observed in the THz and vibration-rotation transitions in the mid-IR range. The slow conversion between para and ortho water allowed us to record the time evolution of spectra and to separate ortho and para absorption lines of water. The similarity of the rotation spectrum of caged water to water in the gas phase indicates that water is free to rotate in the C60 cage even at temperature as low as 3 K. However, spectral lines show a splitting of about 0.5 meV what is not compatible with the icosahedral symmetry of C60. Different models (e.g. crystal field effects in solid C60, C60 cage distortions) will be discussed. This work was supported by institutional research funding IUT23-3 of the Estonian Ministry of Education and Research.

  1. Nanoparticle Fullerene (C60) demonstrated stable binding with antibacterial potential towards probable targets of drug resistant Salmonella typhi - a computational perspective and in vitro investigation.

    Science.gov (United States)

    Skariyachan, Sinosh; Parveen, Asma; Garka, Shruti

    2016-11-23

    Salmonella typhi, a Gram negative bacterium, has become multidrug resistant (MDR) to wide classes of antibacterials which necessitate an alarming precaution. This study focuses on the binding potential and therapeutic insight of Nano-Fullerene C60 towards virulent targets of Salmonella typhi by computational prediction and preliminary in vitro assays. The clinical isolates of Salmonella typhi were collected and antibiotic susceptibility profiles were assessed. The drug targets of pathogen were selected by rigorous literature survey and gene network analysis by various metabolic network resources. Based on this study, 20 targets were screened and the 3D structures of few drug targets were retrieved from PDB and others were computationally predicted. The structures of nanoleads such as Fullerene C60, ZnO and CuO were retrieved from drug databases. The binding potential of these nanoleads towards all selected targets were predicted by molecular docking. The best docked conformations were screened and concept was investigated by preliminary bioassays. This study revealed that most of the isolates of Salmonella typhi were found to be MDR (p Salmonella typhi.

  2. Density Functional Theory and Grand Canonical Monte Carlo Simulations of the Hydrogen Storage Properties of Partially Truncated and Open Cage C60 Fullerenes

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-Dong; TANG Yong-Jian; CHENG Xin-Lu; ZHANG Hong

    2011-01-01

    The potential energies of H2 molecules with partially truncated and open cage C6o fullerenes,including Css,C55,C54(Ⅰ),C54(Ⅱ) and C46,are investigated by means of the density functional theory method.The energy barrier for one H2 molecule (with two postures) entering into the nanocage decreases from 435.59 (513.45)kcal/mol to 3.64 (-2.06) kcal/mol with the increase of the truncated pore.The grand canonical Monte Carlo simulations reveal that each nanocage can accommodate only one H2 molecule inside its cavity at both 77K and 298K.All the other H2 molecules are adsorbed round the truncated pores outside the nanocages.Exceptionally,the truncated C46 can store 2.28wt% H2 molecules at 77K.Therefore,the truncating part of the C60 molecule may be a novel idea to explore C60 fullerene as a hydrogen storage material.Hydrogen is one of the clean and renewable energy carriers used to replace traditional fossil fuels,which have caused great negative effects on the environment.However,the main obstacle for the wide use of hydrogen is its dense and safe storage.[1-3] One proposed method is to physisorbe molecular hydrogen on porous materials.[4-6] Some studies found that metal organic frameworks have the potential to satisfy the goal of gravimetric density of 6wt% hydrogen,[6-9]as set by the U.S.Department of Energy in 2010.However,it is unfortunate that the synthesis of these artificially designed frames is a tremendous obstacle.%The potential energies of H2 molecules with partially truncated and open cage C60 fullerenes, including C58, C55, C54(I), C54(I) and C46, are investigated by means of the density functional theory method. The energy barrier for one H2 molecule (with two postures) entering into the nanocage decreases from 435.59 (513.45) kcal/mol to 3.64 (-2.06) kcal/mol with the increase of the truncated pore. The grand canonical Monte Carlo simulations reveal that each nanocage can accommodate only one H2 molecule inside its cavity at both 77 K and 298 K. All

  3. Ion-Regulated Allosteric Binding of Fullerenes (C-60 and C-70) by Tetrathiafulvalene-Calix[4]pyrroles

    DEFF Research Database (Denmark)

    Davis, C. M.; Lim, J. M.; Larsen, K. R.

    2014-01-01

    crystal X-ray diffraction methods and in dichloromethane solution by means of continuous variation plots and UV-vis spectroscopic titrations. These analyses revealed a 1:1 stoichiometry between the anion-bound TTF-C4Ps and the complexed ftillerenes. The latter guests are bound within the bowl-like cup...... of the two test fullerenes by inducing a conformational change from the 1,3-alternate to the cone conformer of the TTF-C4Ps, thus acting as positive heterotropic allosteric effectors. For a particular halide anion, the choice of tetraalkylammonium salts serves to modulate the strength of the TTF-C4P...

  4. The C60-Fullerene Porphyrin Adducts for Prevention of the Doxorubicin-Induced Acute Cardiotoxicity in Rat Myocardial Cells

    Directory of Open Access Journals (Sweden)

    Seyed Vahid Shetab Boushehri

    2010-10-01

    Full Text Available This is a fullerene-based low toxic nanocationite designed for targeted delivery of the paramagnetic stable isotope of magnesium to the doxorubicin (DXR-induced damaged heart muscle providing a prominent effect close to about 80% recovery of the tissue hypoxia symptoms in less than 24 hrs after a single injection (0.03 - 0.1 LD50. Magnesium magnetic isotope effect selectively stimulates the ATP formation in the oxygen-depleted cells due to a creatine kinase (CK and mitochondrial respiratory chain-focusing "attack" of 25Mg2+ released by nanoparticles. These "smart nanoparticles" with membranotropic properties release the overactivating cations only in response to the intracellular acidosis. The resulting positive changes in the energy metabolism of heart cell may help to prevent local myocardial hypoxic (ischemic disorders and, hence, to protect the heart muscle from a serious damage in a vast variety of the hypoxia-induced clinical situations including DXR side effects.

  5. The C60-Fullerene Porphyrin Adducts for Prevention of the Doxorubicin-Induced Acute Cardiotoxicity in Rat Myocardial Cells

    Directory of Open Access Journals (Sweden)

    Seyed Vahid Shetab Boushehri

    2010-09-01

    Full Text Available "nThis is a fullerene-based low toxic nanocationite designed for targeted delivery of the paramagnetic stable isotope of magnesium to the doxorubicin (DXR-induced damaged heart muscle providing a prominent effect close to about 80% recovery of the tissue hypoxia symptoms in less than 24 hrs after a single injection (0.03 - 0.1 LD50. Magnesium magnetic isotope effect selectively stimulates the ATP formation in the oxygen-depleted cells due to a creatine kinase (CK and mitochondrial respiratory chain-focusing "attack" of 25Mg2+ released by nanoparticles. These "smart nanoparticles" with membranotropic properties release the overactivating cations only in response to the intracellular acidosis. The resulting positive changes in the energy metabolism of heart cell may help to prevent local myocardial hypoxic (ischemic disorders and, hence, to protect the heart muscle from a serious damage in a vast variety of the hypoxia-induced clinical situations including DXR side effects.

  6. Fabrication of highly sensitive and selective nanocomposite film based on CuNPs/fullerene-C60/MWCNTs: An electrochemical nanosensor for trace recognition of paracetamol.

    Science.gov (United States)

    Brahman, Pradeep Kumar; Suresh, Lakkavarapu; Lokesh, Veeramacheneni; Nizamuddin, Syed

    2016-04-21

    Designing an electrochemical sensor for versatile clinical applications is a sophisticated task and how dedicatedly functionalized composite materials can perform on this stage is a challenge for today and tomorrow's Nanoscience and Nanotechnology. In the present work, we demonstrate a new strategy for the development of novel electrochemical sensor based on catalytic nanocomposite film. Fullerene-C60 and multi-walled carbon nanotubes (MWCNTs) were dropped on the pre-treated carbon paste electrode (CPE) and copper nanoparticles (CuNPs) electrochemically deposited on the modified CPE to form nanocomposite film of CuNPs/C60/MWCNTs/CPE. In this work, an electrochemical method based on square wave voltammetry (SWV) employing CuNPs/C60/MWCNTs/CPE has been presented for the recognition and determination of paracetamol (PT). Developed electrochemical sensor was characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronocoulometry. The composite film made the fabricated sensor to display high sensitivity and good selectivity for PT detection. The influence of the optimization parameters such as pH, accumulation time, deposition potential, scan rate and effect of loading of composite mixture of C60-MWCNTs and CuNPs on the electrochemical performance of the sensor were evaluated. A linear range from 4.0 × 10(-9) to 4.0 × 10(-7) M for PT detection was obtained with a detection limit of 7.3 × 10(-11) M. The fabricated sensor was successfully applied to the detection of PT in biological samples with good recovery ranging from 99.21 to 103%.

  7. Formation of substitutionalmetallofullerenes by laser ablation of externally doped fullerenes C60Mx (M=Sm, Pt,Ni and Rh)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Photofragmentation study of metal fullerides C60Mx (M=Sm, Pt, Ni and Rh) by excimer laser ablation-TOF mass spectrometry shows that metallofullerenes C2nM and C2n+1M formed in both the positive and negative ionic medes.The isotopic distributions of the metallofullerenes C2nM and C2n+1M are consistent with the calculated spectra based on the natural abundance of isotopes of C and M, confirming the formation of metallofullerenes. The metal atom is supposed to be incorporated into the network of the fullerene cage to replace one carbon atom of the cage forming substitutional metallofullerene. Odd-numbered high carbon cluisters are observed in our laser ablation study of all the metal fullerides in the negative ion channel. Evolution of mass spectrum with irradiation laser shots shows that the formation of the substitutionally doped fullerenes is closely related to the production of metal carbide (MC). The structures, as well as formation mechanism, of metallofullerenes C2n+1Mand C2nM with even and odd numbers of total atoms respectively are discussed based on the structural optimization of the odd-numbered high carbon clusters.

  8. Optimization of Optical and Electronic properties of Carbon Fullerenes: Symmetry-Reduced C60 and Dumbbell-Like Novel Structures

    Energy Technology Data Exchange (ETDEWEB)

    Manaa, M R

    2008-06-13

    Using quantum chemical density functional calculations, we study two possible pathways for manipulating the optical and electronic properties of all-carbon fullerenes structures. In the first, the optical properties of C{sub 60} are shown to be enhanced via reduction of the perfectly spherical Ih symmetry structure to energetically feasible lower symmetries. A D{sub 3d} symmetry structure of C{sub 60} proved to be 39 meV lower in energy than the Ih conformation. This reduction in symmetry activates otherwise silent modes in the IR and Raman spectra, possibly achievable via solvation effects. In the second pathway, fusing a building block of an-all carbon hexagonal unit as a connector between two C{sub 60} cages is considered. Optimizations on a resulting series of dumbbell-like structures, molecular C{sub 126}, C{sub 132}, C{sub 138}, C{sub 144}, and C{sub 180}, impart distinct variation in the electronic properties of these novel structures with size. These structures are further shown to support stable anionic radical forms.

  9. Properties of the fullerene C60-containing PN Lin49 in the SMC; Explanations of strong near-IR excess

    Science.gov (United States)

    Otsuka, Masaaki; Kemper, Francisca; Leal-Ferreira, Marcelo L.; Aleman, Isabel; Bernard-Salas, Jeronimo; Cami, Jan; Ochsendorf, Bram; Peeters, Els

    2016-07-01

    We performed a detailed spectroscopic analysis of the fullerene C6o-containing planetary nebula (PN) Lin49 in the Small Magellanic Cloud (SMC). Lin49 is a C-rich and metal- deficient PN (Z∼⃒0.0006) and its nebular abundances are in agreement with the AGB model for the initially 1.25Mʘ stars with the metallicity Z = 0.001 of Fishlock et al. (2014, [1]). By stellar absorption fitting with TLUSTY, we derived stellar abundances, effective temperature, and surface gravity. We constructed the photo-ionization model with CLOUDY in order to investigate physical conditions of Lin49. The model with the 0.005-0.1 μm radius graphite and a constant hydrogen density shell could not fit the ∼⃒1-5 μm SED owing to the strong near-IR excess. We propose that the near-IR excess indicates (1) the presence of extremely small carbon molecules or (2) the presence of high-density structure surrounding the central star.

  10. Interaction of Fullerenes with Organosilanes in the Ionization Chamber of a Mass Spectrometer under Electron Impact and the Reaction of C60 with Tetraphenylsilane in Solution under UV Irradiation

    Directory of Open Access Journals (Sweden)

    Yury I. Lyakhovetsky

    2016-01-01

    Full Text Available C60 was shown to react with organosilanes Me4Si, Ph2SiH2, Ph2MeSiH, Ph4Si, and α-naphthylphenylmethylsilane in the electron ionization ion source of a mass spectrometer with the transfer of the corresponding organic radicals (Me, Ph, and α-naphthyl from the silanes to the fullerene. The reactions were accompanied by hydrogen addition to some products and hydrogen loss from them. C70 reacted with Me4Si analogously. A reaction mechanism involving homolytic dissociation of the silanes under electron impact to the corresponding organic radicals, which react further with C60 at the surface of the ionization chamber of the mass spectrometer to give the respective adducts, was offered. A mechanistic study of the reaction of C60 with Me4Si supported it. No silicon containing derivatives of the fullerenes were found. C60 reacted with Ph4Si in solution under UV irradiation in a similar fashion furnishing phenyl derivatives of the fullerene. These results provide an additional support to the hypothesis formulated earlier that the homolytic reactive mass spectrometry of fullerenes (the reactions of fullerenes with other species in the ionization chambers of mass spectrometers and their mass spectral monitoring can predict the reactivity of them toward the same reagents in solution to a significant extent.

  11. Fullerene-C60-MWCNT composite film based ultrasensitive electrochemical sensing platform for the trace analysis of pyruvic acid in biological fluids.

    Science.gov (United States)

    Brahman, Pradeep Kumar; Pandey, Nidhi; Topkaya, Seda Nur; Singhai, Rashmi

    2015-03-01

    We propose development of a novel electrochemical sensor based on fullerene-multi-walled carbon nanotubes composite film for the sensitive determination of the pyruvic acid in biological fluids. The developed sensor was characterized by cyclic voltammetry. The nanocomposite film of C60-MWCNTs on GCE exhibits electrocatalytic activity towards pyruvic acid reduction and also decreases the reduction overpotential. The influence of the optimization parameters such as pH and effect of loading of composite mixture of C60 and MWCNTs on the electrochemical performance of the sensor were evaluated. Various kinetic parameters such as electron transfer number (n=2), proton transfer number (m=2) and charge transfer coefficient (α=0.56) were also calculated. Under optimized conditions, the squarewave reduction peak current was linear over the concentration range of 2.0-55 nM with the detection and quantification limit of 0.1 nM and 0.8 nM respectively. The fabricated sensor was successfully applied to the detection of pyruvic acid in biological samples with good recovery ranging from 97.6% to 103.6%. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. In Silico Olefin Metathesis with Ru-Based Catalysts Containing N-Heterocyclic Carbenes Bearing C60 Fullerenes.

    Science.gov (United States)

    Martínez, Juan Pablo; Vummaleti, Sai Vikrama Chaitanya; Falivene, Laura; Nolan, Steven P; Cavallo, Luigi; Solà, Miquel; Poater, Albert

    2016-05-01

    Density functional theory calculations have been used to explore the potential of Ru-based complexes with 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene (SIMes) ligand backbone (A) being modified in silico by the insertion of a C60 molecule (B and C), as olefin metathesis catalysts. To this end, we investigated the olefin metathesis reaction catalyzed by complexes A, B, and C using ethylene as the substrate, focusing mainly on the thermodynamic stability of all possible reaction intermediates. Our results suggest that complex B bearing an electron-withdrawing N-heterocyclic carbene improves the performance of unannulated complex A. The efficiency of complex B is only surpassed by complex A when the backbone of the N-heterocyclic carbene of complex A is substituted by two amino groups. The particular performance of complexes B and C has to be attributed to electronic factors, that is, the electronic-donating capacity of modified SIMes ligand rather than steric effects, because the latter are predicted to be almost identical for complexes B and C when compared to those of A. Overall, this study indicates that such Ru-based complexes B and C might have the potential to be effective olefin metathesis catalysts.

  13. In Silico Olefin Metathesis with Ru-Based Catalysts Containing N-Heterocyclic Carbenes Bearing C60Fullerenes

    KAUST Repository

    Martínez, Juan Pablo

    2016-04-10

    Density functional theory calculations have been used to explore the potential of Ru-based complexes with 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene (SIMes) ligand backbone (A) being modified in silico by the insertion of a C60 molecule (B and C), as olefin metathesis catalysts. To this end, we investigated the olefin metathesis reaction catalyzed by complexes A, B, and C using ethylene as the substrate, focusing mainly on the thermodynamic stability of all possible reaction intermediates. Our results suggest that complex B bearing an electron-withdrawing N-heterocyclic carbene improves the performance of unannulated complex A. The efficiency of complex B is only surpassed by complex A when the backbone of the N-heterocyclic carbene of complex A is substituted by two amino groups. The particular performance of complexes B and C has to be attributed to electronic factors, that is, the electronic-donating capacity of modified SIMes ligand rather than steric effects, because the latter are predicted to be almost identical for complexes B and C when compared to those of A. Overall, this study indicates that such Ru-based complexes B and C might have the potential to be effective olefin metathesis catalysts. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Influence of surface heterogeneities on reversibility of fullerene (nC60) nanoparticle attachment in saturated porous media.

    Science.gov (United States)

    Shen, Chongyang; Zhang, Mengjia; Zhang, Shuzhen; Wang, Zhan; Zhang, Hongyan; Li, Baoguo; Huang, Yuanfang

    2015-06-15

    This study systematically investigated influence of surface roughness and surface chemical heterogeneity on attachment and detachment of nC60 nanoparticles in saturated porous media by conducting laboratory column experiments. Sand and glass beads were employed as a model collectors to represent a different surface roughness. The two collectors were treated by washing with only deionized water or by using acids to extensively remove chemical heterogeneities. Results show that both attachment and detachment were more in the acid-treated sand than those in the acid-treated glass beads. The greater attachment and detachment were attributed to the reason that sand surfaces have much more nanoscale asperities, which facilitates particle attachment atop of them at primary minima and subsequent detachment upon reduction of ionic strength. No detachment was observed if the water-washed collectors were employed, demonstrating that the couple of chemical heterogeneity with nanoscale roughness causes irreversible attachment in primary minima. Whereas existing studies frequently represented surface rough asperities as regular geometries (e.g., hemisphere, cone, pillar) for estimating influence of surface roughness on Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energies, our theoretical calculations indicate that the assumptions could underestimate both attachment and detachment because these geometries cannot account for surface curvature effects.

  15. Porous polymer monoliths functionalized through copolymerization of a C60 fullerene-containing methacrylate monomer for highly efficient separations of small molecules

    KAUST Repository

    Chambers, Stuart D.

    2011-12-15

    Monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate) and poly(butyl methacrylate-co-ethylene dimethacrylate) capillary columns, which incorporate the new monomer [6,6]-phenyl-C 61-butyric acid 2-hydroxyethyl methacrylate ester, have been prepared and their chromatographic performance have been tested for the separation of small molecules in the reversed phase. While addition of the C60-fullerene monomer to the glycidyl methacrylate-based monolith enhanced column efficiency 18-fold, to 85 000 plates/m at a linear velocity of 0.46 mm/s and a retention factor of 2.6, when compared to the parent monolith, the use of butyl methacrylate together with the carbon nanostructured monomer afforded monolithic columns with an efficiency for benzene exceeding 110 000 plates/m at a linear velocity of 0.32 mm/s and a retention factor of 4.2. This high efficiency is unprecedented for separations using porous polymer monoliths operating in an isocratic mode. Optimization of the chromatographic parameters affords near baseline separation of 6 alkylbenzenes in 3 min with an efficiency of 64 000 plates/m. The presence of 1 wt % or more of water in the polymerization mixture has a large effect on both the formation and reproducibility of the monoliths. Other factors such as nitrogen exposure, polymerization conditions, capillary filling method, and sonication parameters were all found to be important in producing highly efficient and reproducible monoliths. © 2011 American Chemical Society.

  16. Nano-carbon coating layer prepared by the thermal evaporation of fullerene C60 for lithium metal anodes in rechargeable lithium batteries.

    Science.gov (United States)

    Arie, Arenst Andreas; Lee, Joong Kee

    2011-07-01

    A nano carbon coating layer was prepared by the thermal evaporation of fullerene C60 on the surface of lithium metal anodes for rechargeable lithium batteries. The morphology and structure of the carbon layer was firstly investigated by Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effects of the nano-carbon coating layer on the electrochemical performance of the lithium electrode were then examined by charge-discharge tests and impedance spectroscopy. Raman spectra of carbon coating layer showed two main peaks (D and G peaks), indicating the amorphous structure of the film. A honey comb-like structure of carbon film was observed by TEM photographs, providing a transport path for the transport of lithium ions at the electrode/electrolyte interface. The carbon coated lithium electrodes exhibited a higher initial coulombic efficiency (91%) and higher specific capacity retention (88%) after the 30th cycle at 0.2 C-rate between 3.4 and 4.5 V. Impedance measurements showed that the charge transfer resistance was significantly reduced after cycle tests for the carbon coated electrodes, revealing that the more stable solid electrolyte (SEI) layer was established on their surface. Based on the experimental results, it suggested that the presence of the nano-carbon coating layer might suppress the dendritic growth on the surface of lithium metal electrodes, as confirmed by the observation of SEM images after cycle tests.

  17. Distribution and biomarkers of Carbon-14 labeled fullerene C60 ([14C(U)]C60) in female rats and mice for up to 30 days after intravenous exposure

    Science.gov (United States)

    Sumner, Susan C. J.; Snyder, Rodney W.; Wingard, Christopher; Mortensen, Ninell P.; Holland, Nathan A.; Shannahan, Jonathan H.; Dhungana, Suraj; Pathmasiri, Wimal; Han, Li; Lewin, Anita H.; Fennell, Timothy R.

    2016-01-01

    A comprehensive distribution study was conducted in female rats and mice exposed to a suspension of uniformly carbon-14 labeled C60 ([14C(U)]C60). Rodents were administered [14C(U)]C60 (~0.9 mg /kg body weight) or 5% PVP-saline vehicle alone via a single tail vein injection. Tissues were collected at 1 hour, 1, 7, 14 and 30 days after administration. A separate group of rodents received 5 daily injections of suspensions of either [14C(U)]C60 or vehicle with tissue collection 14 days post exposure. Radioactivity was detected in over 20 tissues at all time period. The highest concentration of radioactivity in rodents at each time point was in liver, lungs and spleen. Elimination of [14C(U)]C60 was <2% in urine and feces at any 24 hour time points. [14C(U)]C60 and [14C(U)]C60-retinol were detected in liver of rats and together accounted for ~99% and ~56% of the total recovered at 1 and 30 days post exposure, respectively. The blood radioactivity at 1 hour after [14C(U)]C60 exposure was four-fold higher in rats than in mice; blood radioactivity was still in circulation at 30 days post [14C(U)]C60 exposure in both species (<1%). Levels of oxidative stress markers increased by 5 days after exposure and remained elevated, while levels of inflammation markers initially increased and then returned to control values. The level of cardiovascular marker vWF, increased in rats, but remained at control levels in mice. This study demonstrates that [14C(U)]C60 is retained in female rodents with little elimination by 30 days after i.v. exposure, and leads to systemic oxidative stress. PMID:25727383

  18. Photocycloaddition of anthracene to excited C-60

    Energy Technology Data Exchange (ETDEWEB)

    Gol`dshleger, N.F.; Denisov, N.N.; Lobach, A.S. [and others

    1995-02-01

    The ability to participate in photochemical cycloaddition reactions is characteristic feature of chromophores with a carbon double bond. In this work, the authors demonstrate the formation of an adduct by cycloaddition of anthracene to the triplet-excited C-60 fullerene under anaerobic conditions, which provides a straight forward way to synthesize new derivatives of C-60 fullerenes. Reaction methods, conditions, and mechanisms are included along with the characterization of the fullerene derivative with IR, MS, and NMR methods.

  19. 水溶性C60衍生物的光致细胞膜毒性的动态研究%Dynamic Research of Photo-induced Toxicity against Cell Membrane by a Water-soluble C60 Derivative

    Institute of Scientific and Technical Information of China (English)

    陈霖; 杨新林; 彭鲲鹏; 程福永; 朱鹤孙

    2001-01-01

    用激光共聚焦扫描显微镜研究了在低功率(≤1mW)激光下水溶性C60丙二酸衍生物( D MA C60)对HeLa细胞细胞膜的光诱导损伤及该过程中细胞内钙离子浓度([Ca2+ ]i)的变化 。发现DMA C60对HeLa细胞细胞膜的光诱导损伤过程在低浓度下(≥1μM)即可发生 ,而且 有浓度依赖性。值得注意的是,实验发现在膜损伤发生前伴随细胞内钙离子浓度的瞬时性升 高。这些结果直接证实细胞膜是C60衍生物的光敏作用靶点,并提示钙信号可能参与 这一过程。%By using confocal laser scanning microscope, the photo-induced damage to cell m embrane of HeLa cells by dimalonic acid C60 (DMA C60) was investigat ed in the presence of low powerful laser source (P≤1mW), as well as the c hange of intracellular calcium concentration during the damage. The data showed that t he photo-induced toxicity against cell membrane activity occurred even at the p resence of low concentration of DMA C60 (≥1μ mol/L), and the damage was dose -dependent. Furthermore, it was found that the transient increase of intracellu lar calcium concentration took place before the damage of cell membrane. These r esults demonstrated that cell membrane was a target of photosensitive action pro duced by C60 derivative, and implied that calcium signaling was probably i nvolved in the photosensitive action.

  20. Photoinduced energy and electron transfer in a C-60-6T-C-60 triad

    NARCIS (Netherlands)

    van Hal, P.A.; Langeveld-Voss, B.M.W.; Meskers, S.C.J.; Hummelen, J.C.; Janssen, R.A.J.; Knol, J.

    2001-01-01

    Photoinduced energy and electron transfer in a fullerene-sexithiophene-fullerene (C60-6T-C60) triad in solvents of different polarity is studied using photoinduced absorption (PIA) and photoluminescence (PL) spectroscopy. The polarity of the solvent has an essential role in the formation and

  1. Photophysics of C60 Colloids

    Science.gov (United States)

    2012-11-28

    34Investigation of encapsulation and solvatochromism of fullerenes in binary solvent mixtures," Journal of Physical Chemistry B 103(51), 11256-11260 (1999). 76...E. Huie, P. Neta, H. Hungerbühler, and K.-D. Asmus, "Excitation of C60, solubilized in water by triton X-100 and [gamma]- cyclodextrin , and

  2. Collision dynamics of He@C60+He@C60 at low energies

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A semi-empirical molecular dynamics model is developed. The central collisions of C60+C60 and He@C60+He@C60 at different incident energies are investigated based on this model. It is found that the dimer structures have been produced at proper incident energies and these fullerene dimers could be formed by a self-assembly of C60 fullerene and He@C60. The He atom has a significant effect at higher incident energy and this embedded He atom can enhance the stability of the dimer structure.

  3. An ab-initio density functional theory investigation of fullerene/Zn-phthalocyanine (C60/ZnPc) interface with face-on orientation

    Energy Technology Data Exchange (ETDEWEB)

    Javaid, Saqib [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); National Centre of Physics, Islamabad (Pakistan); Javed Akhtar, M., E-mail: javedakhtar6@gmail.com [EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)

    2015-07-28

    We have employed density functional theory to study the C60/ZnPc interface with face-on orientation, which has recently been tailored experimentally. For this purpose, adsorption of ZnPc on C60 has been studied, while taking into account different orientations of C60. Out of various adsorption sites investigated, 6:6 C-C bridge position in apex configuration of C60 has been found energetically the most favourable one with C60-ZnPc adsorption distance of ∼2.77 Å. The adsorption of ZnPc on C60 ensues both charge re-organization and charge transfer at the interface, resulting in the formation of interface dipole. Moreover, by comparing results with that of C60/CuPc interface, we show that the direction of interface dipole can be tuned by the change of the central atom of the phthalocyanine molecule. These results highlight the complexity of electronic interactions present at the C60/Phthalocyanine interface.

  4. Defensive effects of fullerene-C60 dissolved in squalane against the 2,4-nonadienal-induced cell injury in human skin keratinocytes HaCaT and wrinkle formation in 3D-human skin tissue model.

    Science.gov (United States)

    Kato, Shinya; Aoshima, Hisae; Saitoh, Yasukazu; Miwa, Nobuhiko

    2010-02-01

    We dissolved fullerene-C60 in squalane (LipoFullerene; LF-SQ, C60-eq.: 500 ppm) and examined its defensive effects against 2,4-nonadienal (NDA)-induced cell injury in HaCaT keratinocytes and wrinkle formation in three dimensional (3D)-human skin tissue model. NDA is an analog of 4-hydroxynonenal, one of major causes for human body odor indicative of aging and a lipophilic cell injury factor. Cell viability (% of the control) decreased to 31.6% on treatment with NDA (40 microM), but it increased to 66.0-97.5% when LF-SQ of 1-4% (C60-eq.: 5-20 ppm) was administered for 5 hr before NDA addition. The defensive effect by LF-SQ was superior to that of "squalane" alone at the same doses. NDA-induced DNA-fragmentation in HaCaT cells was suppressed by LF-SQ administered for 5 hr before NDA treatment, and LF-SQ protected HaCaT cells against apoptosis-like cell death. LF-SQ did not appreciably defend against hydrogen peroxide, though LF-SQ effectively defended against tert-butylhydroperoxide, a type of the intermediate hydrophilicity-lipophilicity degree out of other reactive oxygen species. The scanning electron microscopy demonstrated that NDA caused wrinkles and abnormal scales on keratinocytes of 3D-human skin tissue model, and structural homogeneity of the interstratum was broken, any of which were, however, markedly suppressed with LF-SQ. Squalane alone exhibited defensive effect against the skin tissue injury to some extent, but which was inferior to LF-SQ. LF-SQ might effectively capture and scavenge lipid radicals generated inside the cell membrane, because squalane acts as a lipophilic carrier of C60. C60 dissolved in squalane can be expected to serve as a cosmeceutical ingredient for anti-wrinkle formation.

  5. Translocation mechanism of C60 and C60 derivations across a cell membrane

    Science.gov (United States)

    Liang, Lijun; Kang, Zhengzhong; Shen, Jia-Wei

    2016-11-01

    Carbon-based nanoparticles (NPs) such as fullerenes and nanotubes have been extensively studied for drug delivery in recent years. The permeation process of fullerene and its derivative molecules through membrane is essential to the utilization of fullerene-based drug delivery system, but the mechanism and the dynamics of permeation through cell membrane are still unclear. In this study, coarse-grained molecular dynamics simulations were performed to investigate the permeation process of functionalized fullerene molecules (ca. 0.72 nm) through the membrane. Our results show that single functionalized fullerene molecule in such nanoscale could permeate the lipid membrane in micro-second time scale. Pristine C60 molecules prefer to aggregate into several small clusters while C60OH15 molecules could aggregate into one big cluster to permeate through the lipid membrane. After permeation of C60 or its derivatives into membrane, all C60 and C60OH15 molecules disaggregated and monodispersed in the lipid membrane.

  6. Interaction of Fullerenes with Organosilanes in the Ionization Chamber of a Mass Spectrometer under Electron Impact and the Reaction of C60 with Tetraphenylsilane in Solution under UV Irradiation

    OpenAIRE

    Lyakhovetsky, Yury I.; Shilova, Elena A.; Pleshkova, Alexandra P.; Alexander I. Belokon; Yakushin, Sergey O.; Tumanskii, Boris L.

    2016-01-01

    C60 was shown to react with organosilanes Me4Si, Ph2SiH2, Ph2MeSiH, Ph4Si, and α-naphthylphenylmethylsilane in the electron ionization ion source of a mass spectrometer with the transfer of the corresponding organic radicals (Me, Ph, and α-naphthyl) from the silanes to the fullerene. The reactions were accompanied by hydrogen addition to some products and hydrogen loss from them. C70 reacted with Me4Si analogously. A reaction mechanism involving homolytic dissociation of the silanes under ele...

  7. Perturbed Angular Correlation Study of the Static and Dynamic Aspects of Cadmium and Mercury Atoms Inside and Attached to a C60 Fullerene Cage

    CERN Document Server

    Das, Satyendra K; Banerjee, Debasish; Johnston, Karl; Das, Parnika; Butz, Tilman; Amaral, Vitor S; Correia, Joao G; Barbosa, Marcelo B

    2014-01-01

    30 keV Cd-111m and 50 keV Hg-199m beams from ISOLDE were used to implant on preformed targets of C-60 with a thickness of 1 mg cm(-2). Endofullerene compounds, viz. Cd-111m@C-60 and Hg-199m@C-60 formed during implantation were separated by filtration through micropore filter paper followed by solvent extraction. Dried samples of the endofullerene compounds were counted for the time differential perturbed angular correlation (TDPAC) measurement using the coincidence of the 151-245 keV cascade of Cd-111m and the 374 158 keV cascade of Hg-199m on a six LaBr3(Ce) detector system coupled with digital electronics. The results for 111mCd@C60 indicate a single static component (27\\%) and a fast relaxing component (73\\%), the latter implying that the cadmium atom moves rapidly inside the cage at room temperature. The quadrupole interaction frequency and asymmetry parameter of the cadmium atom occupying the static site in C60 are omega(Q) = 8.21(36) Mrad s(-1) and eta = 0.41(9), respectively. The fast relaxation con...

  8. What is C60. C60 no shotai wa

    Energy Technology Data Exchange (ETDEWEB)

    Osawa, E. (Toyohashi University of Technology, Aichi (Japan))

    1993-03-25

    This paper elucidates what C60 really is. C60(1) is a carbon cluster of a special structure with Cs bonded solidly, and is a molecule chemically. Sixty Sp[sup 2] mixed carbon atoms are distributed evenly on a sphere with a radius of 7[angstrom]. Molecules in a crystal are of nearly perfect sphere, with small inter-molecular contact and weak binding force, and spinning at more than one billion rotations per second. C60 is a carbon's fourth allotrope. Three types of modification have been known to date, including the rugby ball shaped fullerene. Fullerene has been studied actively resulting in successive new reports. It is manufactured basically using the Kraetchmer's resistive heating method at a yield of approximately 10%. A plasma discharge process and an improved laser irradiation process can raise the yield to as high as 20% or more. Industrial application of C60 is within reach. Developmental researches are being moved forward by private corporations in Japan. Its application may cover wide areas, including electric conductors, semiconductors and the like. Elucidation of its production mechanisms has been waited for, together with solving a problem of reducing C60 reagent price. 45 refs., 3 figs.

  9. Buckminsterfullerene's (C60) octanol-water partition coefficient (Kow) and aqueous solubility.

    Science.gov (United States)

    Jafvert, Chad T; Kulkarni, Pradnya P

    2008-08-15

    To assess the risk and fate of fullerene C60 in the environment, its water solubility and partition coefficients in various systems are useful. In this study, the log Kow of C60 was measured to be 6.67, and the toluene-water partition coefficient was measured at log Ktw = 8.44. From these values and the respective solubilities of C60 in water-saturated octanol and water-saturated toluene, C60's aqueous solubility was calculated at 7.96 ng/L(1.11 x 10(-11) M) for the organic solvent-saturated aqueous phase. Additionally, the solubility of C60 was measured in mixtures of ethanol-water and tetrahydrofuran-water and modeled with Wohl's equation to confirm the accuracy of the calculated solubility value. Results of a generator column experiment strongly support the hypothesis that clusters form at aqueous concentrations below or near this calculated solubility. The Kow value is compared to those of other hydrophobic organic compounds, and bioconcentration factors for C60 were estimated on the basis of Kow.

  10. New concepts and applications in the macromolecular chemistry of fullerenes.

    Science.gov (United States)

    Giacalone, Francesco; Martín, Nazario

    2010-10-08

    A new classification on the different types of fullerene-containing polymers is presented according to their different properties and applications they exhibit in a variety of fields. Because of their interest and novelty, water-soluble and biodegradable C(60)-polymers are discussed first, followed by polyfullerene-based membranes where unprecedented supramolecular structures are presented. Next are compounds that involve hybrid materials formed from fullerenes and other components such as silica, DNA, and carbon nanotubes (CNTs) where the most recent advances have been achieved. A most relevant topic is still that of C(60)-based donor-acceptor (D-A) polymers. Since their application in photovoltaics D-A polymers are among the most realistic applications of fullerenes in the so-called molecular electronics. The most relevant aspects in these covalently connected fullerene/polymer hybrids as well as new concepts to improve energy conversion efficiencies are presented.The last topics disccused relate to supramolecular aspects that are in involved in C(60)-polymer systems and in the self-assembly of C(60)-macromolecular structures, which open a new scenario for organizing, by means of non-covalent interactions, new supramolecular structures at the nano- and micrometric scale, in which the combination of the hydrofobicity of fullerenes with the versatility of the noncovalent chemistry afford new and spectacular superstructures.

  11. Effects of fullerene (C60), multi-wall carbon nanotubes (MWCNT), single wall carbon nanotubes (SWCNT) and hydroxyl and carboxyl modified single wall carbon nanotubes on riverine microbial communities.

    Science.gov (United States)

    Lawrence, J R; Waiser, M J; Swerhone, G D W; Roy, J; Tumber, V; Paule, A; Hitchcock, A P; Dynes, J J; Korber, D R

    2016-05-01

    Commercial production of nanoparticles (NP) has created a need for research to support regulation of nanotechnology. In the current study, microbial biofilm communities were developed in rotating annular reactors during continuous exposure to 500 μg L(-1) of each nanomaterial and subjected to multimetric analyses. Scanning transmission X-ray spectromicroscopy (STXM) was used to detect and estimate the presence of the carbon nanomaterials in the biofilm communities. Microscopy observations indicated that the communities were visibly different in appearance with changes in abundance of filamentous cyanobacteria in particular. Microscale analyses indicated that fullerene (C60) did not significantly (p < 0.05) impact algal, cyanobacterial or bacterial biomass. In contrast, MWCNT exposure resulted in a significant decline in algal and bacteria biomass. Interestingly, the presence of SWCNT products increased algal biomass, significantly in the case of SWCNT-COOH (p < 0.05) but had no significant impact on cyanobacterial or bacterial biomass. Thymidine incorporation indicated that bacterial production was significantly reduced (p < 0.05) by all nanomaterials with the exception of fullerene. Biolog assessment of carbon utilization revealed few significant effects with the exception of the utilization of carboxylic acids. PCA and ANOSIM analyses of denaturing gradient gel electrophoresis (DGGE) results indicated that the bacterial communities exposed to fullerene were not different from the control, the MWCNT and SWNT-OH differed from the control but not each other, whereas the SWCNT and SWCNT-COOH both differed from all other treatments and were significantly different from the control (p < 0.05). Fluorescent lectin binding analyses also indicated significant (p < 0.05) changes in the nature and quantities of exopolymer consistent with changes in microbial community structure during exposure to all nanomaterials. Enumeration of protozoan grazers

  12. Fullerenes

    CERN Document Server

    Ehrenreich, Henry

    1994-01-01

    Fullerenes or"buckyballs,"a new carbon-based family of materials, have fascinated the scientific community for the past few years. These materials are likely to find applications ranging from lubricants to batteries to biological magic bullets, which will be of great importance in the science and technology of the next century. This carefully edited volume, the first to include Frans Spaepen as co-editor, summarizes our present understanding in a series of didacticarticles, which take the reader from the fundamentals to the present cutting-edge research. A general overview is followed by chapters devoted to synthesis and characterization of fullerenes and their derivatives, the novel structural properties of buckyballs, tubes, and buckyonions, a theoretical and experimental view of electrons and phonons, and finally to the fascinating superconducting properties of these materials.Key Features* Presents systematic overview of entire field* Discusses synthesis, characterization, structure, and superconducting p...

  13. Carbon nanomaterials: Biologically active fullerene derivatives

    Directory of Open Access Journals (Sweden)

    Bogdanović Gordana

    2016-01-01

    Full Text Available Since their discovery, fullerenes, carbon nanotubes, and graphene attract significant attention of researches in various scientific fields including biomedicine. Nano-scale size and a possibility for diverse surface modifications allow carbon nanoallotropes to become an indispensable nanostructured material in nanotechnologies, including nanomedicine. Manipulation of surface chemistry has created diverse populations of water-soluble derivatives of fullerenes, which exhibit different behaviors. Both non-derivatized and derivatized fullerenes show various biological activities. Cellular processes that underline their toxicity are oxidative, genotoxic, and cytotoxic responses. The antioxidant/cytoprotective properties of fullerenes and derivatives have been considered in the prevention of organ oxidative damage and treatment. The same unique physiochemical properties of nanomaterials may also be associated with potential health hazards. Non-biodegradability and toxicity of carbon nanoparticles still remain a great concern in the area of biomedical application. In this review, we report on basic physical and chemical properties of carbon nano-clusters - fullerenes, nanotubes, and graphene - their specificities, activities, and potential application in biological systems. Special emphasis is given to our most important results obtained in vitro and in vivo using polyhydroxylated fullerene derivative C60(OH24. [Projekat Ministarstva nauke Republike Srbije, br. III45005

  14. UV-Vis diagnostics of the pmma-c 60 composite system and the kinetics of its thermal decomposition

    OpenAIRE

    Bogdanov, A. A.; VOZNYAKOVSKII A.P.; POZDNYAKOV A.O.

    2014-01-01

    The influence of polymer-fullerene interactions and fullerene aggregation on the thermal stability of polymethyl-methacrylate-fullerene C 60 nanocomposite has been studied by means of thermal desorption mass-spectrometry and the UV-Vis absorption spectroscopy.

  15. UV-VIS DIAGNOSTICS OF THE PMMA-C 60 COMPOSITE SYSTEM AND THE KINETICS OF ITS THERMAL DECOMPOSITION

    OpenAIRE

    Bogdanov, A A; VOZNYAKOVSKII A.P.; POZDNYAKOV A.O.

    2014-01-01

    The influence of polymer-fullerene interactions and fullerene aggregation on the thermal stability of polymethyl-methacrylate-fullerene C 60 nanocomposite has been studied by means of thermal desorption mass-spectrometry and the UV-Vis absorption spectroscopy.

  16. Synthesis of cystine C60 derivative and its protective effects on hydrogen peroxide-induced apoptosis in PC12 cells

    Institute of Scientific and Technical Information of China (English)

    Zhen Hu; Hai Ping Xing; Zhou Zhu; Wei Wang; Wen Chao Guan

    2007-01-01

    Oxidative stress has been considered as a major cause of cellular injuries in a variety of clinical abnormalities, especially prominent in neural diseases. One of the usable ways to prevent the reactive oxygen species (ROS)-mediated cellular injury is dietary or pharmaceutical augmentation of some free radical scavenger. Water-soluble amino-fullerene is a novel compound that behaves as a free radical scavenger with excellent biology consistent. In the present study, we have synthesized and characterized a novel cystine C60 derivative for the first time, and investigated the effects on hydrogen peroxide-induced oxidative stress and apoptotic death in cultured rat pheochromocytoma (PC12) cells. PC12 cells treated with hydrogen peroxide underwent apoptotic death as determined by MTT, PI/Hoechst 33342 staining and flow cytometry analysis. These results suggested that cystine C60 derivative has the potential to prevent oxidative stress-induced cell death and has no evident toxicity.

  17. Structure and electronic properties of alkali-C60 nanoclusters.

    Science.gov (United States)

    Rabilloud, Franck

    2010-07-08

    I investigated the structural and electronic properties of both Na(n)C(60) and Li(n)C(60) (n alkali atoms over the C(60) surface is analyzed. The hypotheses for either an homogeneous coating of the C(60) surface by the alkali atoms or the growth of an alkali droplet not wetting the fullerene surface are discussed. Lithium atoms are found to coat homogeneously the fullerene on the C(60) surface via pentagonal sites, contrary to sodium atoms, which prefer to form 4-atom islands on the surface. The charge transfer, the energetics, and the dipole moments are discussed in relation with available results. The adsorption of alkali atoms on the C(60) surface considerably enhances the capacity of C(60) to accept electrons. The arrangement of lithium atoms seems more favorable for the hydrogen storage than that of sodium atoms.

  18. C-60 complexation revisited

    NARCIS (Netherlands)

    Williams, R.M.; Verhoeven, J.M.

    1994-01-01

    In the recent paper by Atwood et al. (Nature 368, 229-231, 1994) on a purification procedure for C60 and C70 by selective complexation with calixarenes, it was implied that we had previously studied the complexation of C60 with cyclodextrins (Williams, R. M. & Verhoeven, J. W., Recl. Trav. Chim.

  19. Solubility of C60 in solvent mixtures.

    Science.gov (United States)

    Kulkarni, Pradnya P; Jafvert, Chad T

    2008-02-01

    The potential large-scale production of fullerene C60 and its widespread use in consumer products may translate into occupational and public exposure and in long-term environmental exposure. To assess the risk and fate of C60 in the environment, it is important to understand its solvate formation in common industrial solvents as the solvates may affect various properties of C60 including reactivity and toxicity, particularly when solvates occur in C60 clusters. In this study, the solubility measurements in mixed solvent system can provide useful information about solvate formation. The solubility of C60 was measured in pure toluene, tetrahydrofuran, ethanol, and acetonitrile to be 3000, 11, 1.4, and 0.04 mg/L, respectively. Additionally, the solubility of C60 was measured in mixtures of toluene-acetonitrile, toluene-ethanol, toluene-tetrahydrofuran, and acetonitrile-tetrahydrofuran. The solubility data were modeled with some accuracy using Wohl's equation. The estimated crystal energy term for C60 in tetrahydrofuran was different than that in the other solvents, indicating that the C60 solid phase in equilibrium with tetrahydrofuran solution may be a solvated crystal.

  20. Adsorption of $^4$He on a single C$_{60}$

    OpenAIRE

    Szybisz, Leszek; Urrutia, Ignacio

    2003-01-01

    The adsorption of $^4$He inside and outside a single fullerene C$_{60}$ is studied. A physisorption potential is proposed. The energetics and structural features of C$_{60}$-$^4$He$_N$ clusters are investigated. Particular attention is paid to the growth of the highly pronounced layered density profile. The evolution towards bulk liquid and surface thickness at the free interface are discussed.

  1. Adsorption of 4He on a Single C60

    Science.gov (United States)

    Szybisz, L.; Urrutia, I.

    2004-01-01

    The adsorption of $^4$He inside and outside a single fullerene C$_{60}$ is studied. A physisorption potential is proposed. The energetics and structural features of C$_{60}$-$^4$He$_N$ clusters are investigated. Particular attention is paid to the growth of the highly pronounced layered density profile. The evolution towards bulk liquid and surface thickness at the free interface are discussed.

  2. Structure and Properties of Micro-/nano-sized Electrospum Fullerene/PMMA Mats%电纺C60/PMMA微纳米纤维的结构与性能研究

    Institute of Scientific and Technical Information of China (English)

    贾清秀; 李小宁; 付中玉; 杨中开; 李从举

    2008-01-01

    C60和PMMA溶于甲苯和DMF混合溶剂中,电纺铺备了不同C60含量的PMMA膜,并用SEM、紫外吸收光谱(UV)、X-射线衍射(XRD)、荧光显微镜等对所制电纺膜进行了表征.研究发现,所得C60/PMMA电纺膜中,以纳米纤维为主,有少量微米纤维存在,纤维平均直径约为600 nm;C60的紫外吸收特征明显,且相对其在正己烷中的谱图略有红移;C60在PMMA中的分布比较均匀,可以观察到明显的荧光效应.

  3. Synthesis of decacationic [60]fullerene decaiodides giving photoinduced production of superoxide radicals and effective PDT-mediation on antimicrobial photoinactivation.

    Science.gov (United States)

    Wang, Min; Maragani, Satyanarayana; Huang, Liyi; Jeon, Seaho; Canteenwala, Taizoon; Hamblin, Michael R; Chiang, Long Y

    2013-05-01

    We report a novel class of highly water-soluble decacationic methano[60]fullerene decaiodides C60[>M(C3N6(+)C3)2]-(I(-))10 [1-(I(-))10] capable of co-producing singlet oxygen (Type-II) and highly reactive hydroxyl radicals, formed from superoxide radicals in Type-I photosensitizing reactions, upon illumination at both UVA and white light wavelengths. The O2(-)·-production efficiency of 1-(I(-))10 was confirmed by using an O2(-)·-reactive bis(2,4-dinitrobenzenesulfonyl)tetrafluorofluorescein probe and correlated to the photoinduced electron-transfer event going from iodide anions to (3)C60*[>M(C3N6(+)C3)2] leading to C60(-)·[>M(C3N6(+)C3)2]. Incorporation of a defined number (ten) of quaternary ammonium cationic charges per C60 in 1 was aimed to enhance its ability to target pathogenic Gram-positive and Gram-negative bacterial cells. We used the well-characterized malonato[60]fullerene diester monoadduct C60[>M(t-Bu)2] as the starting fullerene derivative to provide a better synthetic route to C60[>M(C3N6(+)C3)2] via transesterification reaction under trifluoroacetic acid catalyzed conditions. These compounds may be used as effective photosensitizers and nano-PDT drugs for photoinactivation of pathogens.

  4. Extraction and HPLC- UV Analysis of C60, C70, and [6,6]-phenyl C61-butyric acid methyl ester in Synthetic and Natural Waters

    Science.gov (United States)

    Studies have shown that C60 fullerene can form stable colloidal suspensions in water that result in C60 aqueous concentrations many orders of magnitude above C60's aqueous solubility; however, quantitative methods for the analysis of C60 and other fullerenes in environmental medi...

  5. Laser Induced C60 Cage Opening Studied by Semiclassical Dynamics Simulation

    Directory of Open Access Journals (Sweden)

    Yusheng Dou

    2011-01-01

    Full Text Available Laser induced opening of the C60 cage is studied by a semiclassical electron-radiation-ion dynamics technique. The simulation results indicate that the C60 cage is abruptly opened immediately after laser excitation. The opening of the C60 cage induces a quick increase in kinetic energy and a sharp decrease in electronic energy, suggesting that the breaking of the C60 cage efficiently heats up the cluster and enhances the thermal fragmentation of C60 fullerene.

  6. Solubility of C60 and PCBM in Organic Solvents.

    Science.gov (United States)

    Wang, Chun I; Hua, Chi C

    2015-11-12

    The ability to correlate fullerene solubility with experimentally or computationally accessible parameters can significantly facilitate nanotechnology nowadays for a wide range of applications, while providing crucial insight into optimum design of future fullerene species. To date, there has been no single relationship that satisfactorily describes the existing data clearly manifesting the effects of solvent species, system temperature, and isomer. Using atomistic molecular dynamics simulations on two standard fullerene species, C60 and PCBM ([6,6]-phenyl-C61-butyric acid methyl ester), in a representative series of organic solvent media (i.e., chloroform, toluene, chlorobenzene, 1,3-dichlorobenzene, and 1,2-dichlorobenzene), we show that a single time constant characterizing the dynamic stability of a tiny (angstrom-sized) solvation shell encompassing the fullerene particle can be utilized to effectively capture the known trends of fullerene solubility as reported in the literature. The underlying physics differs substantially between the two fullerene species, however. Although C60 was previously shown to be dictated by a diffusion-limited aggregation mechanism, the side-chain-substituted PCBM is demonstrated herein to proceed with an analogous reaction-limited aggregation with the "reaction rate" set by the fullerene rotational diffusivity in the medium. The present results suggest that dynamic quantities-in contrast to the more often employed, static ones-may provide an excellent means to characterize the complex (entropic and enthalpic) interplay between fullerene species and the solvent medium, shed light on the factors determining the solvent quality of a nanoparticle solution, and, in particular, offer a practical pathway to foreseeing optimum fullerene design and fullerene-solvent interactions.

  7. Functionalized fullerene (C₆₀) as a potential nanomediator in the fabrication of highly sensitive biosensors.

    Science.gov (United States)

    Afreen, Sadia; Muthoosamy, Kasturi; Manickam, Sivakumar; Hashim, Uda

    2015-01-15

    Designing a biosensor for versatile biomedical applications is a sophisticated task and how dedicatedly functionalized fullerene (C60) can perform on this stage is a challenge for today and tomorrow's nanoscience and nanotechnology. Since the invention of biosensor, many ideas and methods have been invested to upgrade the functionality of biosensors. Due to special physicochemical characteristics, the novel carbon material "fullerene" adds a new dimension to the construction of highly sensitive biosensors. The prominent aspects of fullerene explain its outstanding performance in biosensing devices as a mediator, e.g. fullerene in organic solvents exhibits five stages of reversible oxidation/reduction, and hence fullerene can work either as an electrophile or nucleophile. Fullerene is stable and its spherical structure produces an angle strain which allows it to undergo characteristic reactions of addition to double bonds (hybridization which turns from sp(2) to sp(3)). Research activities are being conducted worldwide to invent a variety of methods of fullerene functionalization with a purpose of incorporating it effectively in biosensor devices. The different types of functionalization methods include modification of fullerene into water soluble derivatives and conjugation with enzymes and/or other biomolecules, e.g. urease, glucose oxidase, hemoglobin, myoglobin (Mb), conjugation with metals e.g. gold (Au), chitosan (CS), ferrocene (Fc), etc. to enhance the sensitivity of biosensors. The state-of-the-art research on fullerene functionalization and its application in sensor devices has proven that fullerene can be implemented successfully in preparing biosensors to detect glucose level in blood serum, urea level in urine solution, hemoglobin, immunoglobulin, glutathione in real sample for pathological purpose, to identify doping abuse, to analyze pharmaceutical preparation and even to detect cancer and tumor cells at an earlier stage. Employing fullerene

  8. Information Entropy of Fullerenes.

    Science.gov (United States)

    Sabirov, Denis Sh; Ōsawa, Eiji

    2015-08-24

    The reasons for the formation of the highly symmetric C60 molecule under nonequilibrium conditions are widely discussed as it dominates over numerous similar fullerene structures. In such conditions, evolution of structure rather than energy defines the processes. We have first studied the diversity of fullerenes in terms of information entropy. Sorting 2079 structures from An Atlas of Fullerenes [ Fowler , P. W. ; Manolopoulos , D. E. An Atlas of Fullerenes ; Oxford : Clarendon , 1995 . ], we have found that the information entropies of only 14 fullerenes (entropy, i.e., an exclusive compound among the other members of the fullerene family. Such an efficient sorting demonstrates possible relevance of information entropy to chemical processes. For this reason, we have introduced an algorithm for calculating changes in information entropy at chemical transformations. The preliminary calculations of changes in information entropy at the selected fullerene reactions show good agreement with thermochemical data.

  9. Laser-assisted deposition of thin C60 films

    DEFF Research Database (Denmark)

    Schou, Jørgen; Canulescu, Stela; Fæster, Søren

    bound carbon molecule with a well-defined mass (M = 720 amu) and therefore a good, organic test molecule. C60 fullerene thin films of average thickness of more than 100 nm was produced in vacuum by matrix-assisted pulsed laser evaporation (MAPLE). A 355 nm Nd:YAG laser was directed onto a frozen target...

  10. Bioapplication and activity of fullerenol C60(OH)24

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-29

    Dec 29, 2008 ... composed of carbon atoms - fullerenes and their derivatives. One of the ... irradiation of C60 and converts almost quantitatively into a longer-lived triplet state. ... usually inhibited by the presence of singlet oxygen quen- chers (Prat et al., ..... nitrogen dioxide, ozone, paraquat, hyperoxia, carbon tetrachloride ...

  11. C$_{60}$ in Photodissociation Regions

    CERN Document Server

    Castellanos, Pablo; Sheffer, Yaron; Wolfire, Mark G; Tielens, Alexander G G M

    2014-01-01

    Recent studies have confirmed the presence of buckminsterfullerene (C$_{60}$) in different interstellar and circumstellar environments. However, several aspects regarding C$_{60}$ in space are not well understood yet, such as the formation and excitation processes, and the connection between C$_{60}$ and other carbonaceous compounds in the interstellar medium, in particular polycyclic aromatic hydrocarbons (PAHs). In this paper we study several photodissociation regions (PDRs) where C$_{60}$ and PAHs are detected and the local physical conditions are reasonably well constrained, to provide observational insights into these questions. C$_{60}$ is found to emit in PDRs where the dust is cool ($T_d = 20-40$ K) and even in PDRs with cool stars. These results exclude the possibility for C$_{60}$ to be locked in grains at thermal equilibrium in these environments. We observe that PAH and C$_{60}$ emission are spatially uncorrelated and that C$_{60}$ is present in PDRs where the physical conditions (in terms of radi...

  12. C60 1,1,2,2-tetrachloroethylene tetrasolvate

    Directory of Open Access Journals (Sweden)

    C. Arunkumar

    2008-01-01

    Full Text Available In the title complex, C60·4C2Cl4, the C60 molecule is located on an inversion centre and there are two tetrachloroethylene (TCE molecules in the asymmetric unit. Both TCE molecules show positional disorder, with occupancy ratios of 0.75:0.25 and 0.56:0.44. Four fullerene C atoms form short contacts [3.208 (17 and 3.223 (17 Å] with the centres of the TCE double bonds, indicating that C60–solvent interactions are largely π–π in nature.

  13. Nanocomposite Materials of Alternately Stacked C60 Monolayer and Graphene

    Directory of Open Access Journals (Sweden)

    Makoto Ishikawa

    2010-01-01

    Full Text Available We synthesized the novel nanocomposite consisting alternately of a stacked single graphene sheet and a C60 monolayer by using the graphite intercalation technique in which alkylamine molecules help intercalate large C60 molecules into the graphite. Moreover, it is found that the intercalated C60 molecules can rotate in between single graphene sheets by using C13 NMR measurements. This preparation method provides a general way for intercalating huge fullerene molecules into graphite, which will lead to promising materials with novel mechanical, physical, and electrical properties.

  14. High-efficiency palladium catalysts supported on ppy-modified C60 for formic acid oxidation.

    Science.gov (United States)

    Bai, Zhengyu; Yang, Lin; Guo, Yuming; Zheng, Zhi; Hu, Chuangang; Xu, Pengle

    2011-02-14

    A facile preparation of polypyrrole-modified fullerene supported Pd nanoparticles catalyst is introduced; electrochemical measurements demonstrate that the obtained Pd/ppy-C(60) catalyst shows a good electrocatalytic activity and stability for the oxidation of formic acid.

  15. First-principles investigation of organic photovoltaic materials C60, C70, [C60]PCBM , and bis-[C60]PCBM using a many-body G0W0 -Lanczos approach

    Science.gov (United States)

    Qian, Xiaofeng; Umari, Paolo; Marzari, Nicola

    2015-06-01

    We present a first-principles investigation of the excited-state properties of electron acceptors in organic photovoltaics including C60, C70, [6,6]-phenyl-C61-butyric-acid-methyl-ester ([C60]PCBM ), and bis-[C60]PCBM using many-body perturbation theory within the Hedin's G0W0 approximation and an efficient Lanczos approach. Calculated vertical ionization potentials (VIP) and vertical electron affinities (VEA) of C60 and C70 agree very well with experimental values measured in the gas phase. The density of states of all three molecules is also compared to photoemission and inverse photoemission spectra measured on thin films, and they exhibit a close agreement—a rigid energy-gap renormalization owing to intermolecular interactions in the thin films. In addition, it is shown that the low-lying unoccupied states of [C60]PCBM are all derived from the highest-occupied molecular orbitals and the lowest-unoccupied molecular orbitals of fullerene C60. The functional side group in [C60]PCBM introduces a slight electron transfer to the fullerene cage, resulting in small decreases of both VIP and VEA. This small change of VEA provides a solid justification for the increase of open-circuit voltage when replacing fullerene C60 with [C60]PCBM as the electron acceptor in bulk heterojunction polymer solar cells.

  16. Fullerenol C60(OH)24 nanoparticles decrease relaxing effects of dimethyl sulfoxide on rat uterus spontaneous contraction

    Science.gov (United States)

    Slavic, Marija; Djordjevic, Aleksandar; Radojicic, Ratko; Milovanovic, Slobodan; Orescanin-Dusic, Zorana; Rakocevic, Zlatko; Spasic, Mihajlo B.; Blagojevic, Dusko

    2013-05-01

    Dimethyl sulfoxide (DMSO) is a widely used solvent and cryoprotectant that can cause impaired blood flow, reduction in intracranial pressure, tissue edema, inflammatory reactions, inhibition of vascular smooth muscle cell migration and proliferation, processes which can lead to atherosclerosis of the coronary, peripheral and cerebral circulation. Although the adverse effects are rare when DMSO is administered in clinically established concentrations, there is no safe antagonist for an overdose. In this work, we treated isolated spontaneous and calcium-induced contractile active rat uteri (Wistar, virgo intacta), with DMSO and fullerenol C60(OH)24 nanoparticle (FNP) in DMSO. FNP is a water-soluble derivative of fullerene C60. Its size is a 1.1 nm in diameter and is a very promising candidate for a drug carrier in nanomedicine. FNP also displays free radical scavenging activity. DMSO decreased both spontaneous and calcium-induced contractions. In contrast, FNP only decreased spontaneous contraction. FNP decreased copper-zinc superoxide dismutase activity and prevented the DMSO-induced increase in glutathione reductase activity. Atomic force microscopy detected that FNP aggregated with calcium ions. Our results indicate that FNP has properties that make it a good candidate to be a modulator of DMSO activity which could minimize side effects of the latter.

  17. Hierarchical aqueous self-assembly of C60 nano-whiskers and C60-silver nano-hybrids under continuous flow.

    Science.gov (United States)

    Iyer, K Swaminathan; Raston, Colin L; Saunders, Martin

    2007-09-01

    The ubiquitous starch-iodine complex can be used to organize hydrophobic fullerene C(60) in water into nano-whiskers shrouded by the biopolymer, and are approximately 5-8 nm in cross section, and 250-350 nm in length, as a hierarchical self assembly process. The preformed starch-iodine complex reacts with solid pristine C(60) affording nano-whiskers with iodine surrounding the fullerene array, the iodine then being removed on treatment with ascorbic acid. The hydrophobic surface of the nano-whiskers of C(60) can be coated with silver metal in a controlled way using 'soft energy' spinning disc processing.

  18. Interstellar and circumstellar fullerenes

    CERN Document Server

    Bernard-Salas, J; Jones, A P; Peeters, E; Micelotta, E R; Otsuka, M; Sloan, G C; Kemper, F; Groenewegen, M

    2014-01-01

    Fullerenes are a particularly stable class of carbon molecules in the shape of a hollow sphere or ellipsoid that might be formed in the outflows of carbon stars. Once injected into the interstellar medium (ISM), these stable species survive and are thus likely to be widespread in the Galaxy where they contribute to interstellar extinction, heating processes, and complex chemical reactions. In recent years, the fullerene species C60 (and to a lesser extent C70) have been detected in a wide variety of circumstellar and interstellar environments showing that when conditions are favourable, fullerenes are formed efficiently. Fullerenes are the first and only large aromatics firmly identified in space. The detection of fullerenes is thus crucial to provide clues as to the key chemical pathways leading to the formation of large complex organic molecules in space, and offers a great diagnostic tool to describe the environment in which they reside. Since fullerenes share many physical properties with PAHs, understand...

  19. Synthesis of water-soluble C60 derivatives and their scavenging free radical activity

    Institute of Scientific and Technical Information of China (English)

    尹桂; 徐正

    2002-01-01

    Four piperazine-appended [60] fuilerenes (1a-1d) were synthesized and characterized. Their activities of scavenging radical were studied via UV-Vis and EPR. The results indicate that light irradiation is of advantage to increase the activity of scavenging radical.

  20. Thermoelectric properties of Bi0.5Sb1.5Te3/C60 nanocomposites

    NARCIS (Netherlands)

    Blank, V.D.; Buga, S.G.; Kulbachinskii, V.A.; Kytin, V.G.; Medvedev, V.V.; Popov, Y.M.; Stepanov, P.B.; Skok, V.F.

    2012-01-01

    A thermoelectric nanocomposite of Bi0.5Sb1.5Te3 with the C60 fullerene molecules has been synthesized and studied. The fullerene molecules provide the phonons blocking, reducing the lattice thermal conductivity. The reduction of the electrical conductivity is much less than the heat conductivity red

  1. C60的氧化反应研究%Studies on Oxidation Reaction of C60

    Institute of Scientific and Technical Information of China (English)

    李旭; 孔庆宇; 等

    2001-01-01

    Two oxidation products of the reaction of C60 with O3 in toluene or dichlorobenzene were obtained in dependence on the amount of ozone absorbed by the solution and the reaction time. The short time oxidized product is insoluble in common organic solvents and water, but the water-soluble derivatives were obtained after hydrolysis under a basic condition. It′s IR spectrum is similar with that of C60 polyhydric derivatives. The extensive oxidation product of C60 is water-soluble without any further dispose. The structures of the two oxidized products were characterized by variable-temperature FTIR, XPS, elementary analysis, TGA and TOF-MS, ESI-MS, FAB-MS technique. Both products are thermally unstable, H2O, CO and CO2 are eliminated during the increase of temperature.%在C60的甲苯或二氯苯溶液中通入O3,通过改变O3的吸收量及反应时间可得到两种氧化产物. 一种产物在有机溶剂及水中均不溶,但经碱性水解后得到水溶性产物,其红外光谱与C60羟基化合物相似;在长时间通O3条件下,得到水溶性的C60氧化产物. 用变温红外光谱、 XPS、元素分析、热谱和质谱研究了氧化产物的可能结构,发现生成的C60氧化产物对热不稳定,随着温度升高,有CO2, CO和H2O放出.

  2. Processing of C60 thin films by Matrix-Assisted Pulsed Laser Evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    2011-01-01

    Thin films of fullerenes (C60) were deposited onto silicon using matrix-assisted pulsed laser evaporation (MAPLE). The deposition was carried out from a frozen homogeneous dilute solution of C60 in anisole (0.67 wt%), and over a broad range of laser fluences, from 0.15 J/cm2 up to 3.9 J/cm2. MAPLE...

  3. Molecular modeling of C 60:cobaltocene and nickelocene complexes, comparison with IR absorption

    Science.gov (United States)

    Byszewski, P.; Antonova, K.; Kowalska, E.; Radomska, J.; Baran, J.

    2000-06-01

    C 60 was reacted with cobaltocene and nickelocene. The samples of the composition C 60(Cocp 2) 3 and C 60Nicp 2 were obtained in the reaction. Their thermal stability was measured by Thermogravimetry and Differential Scanning Calorimetry and the vibrational spectrum was investigated by infrared absorption. Hydrocarbon groups may be evacuated from the reaction products by annealing, while metal atoms remain dispersed between fullerenes. The experiments are compared with the molecular modeling results obtained by applying the PM3 model.

  4. Self-assembled C60 layers on incommensurate Cu/Si(111)'pseudo-5 × 5' surface

    Science.gov (United States)

    Olyanich, D. A.; Mararov, V. V.; Utas, T. V.; Zotov, A. V.; Saranin, A. A.

    2015-12-01

    Self-assembled growth of C60 monolayers on the pristine and Ge-modified Cu/Si(111)'pseudo-5 × 5' surfaces was studied using scanning tunneling microscopy observations. The pristine Cu/Si(111)'pseudo-5 × 5' surface shows up as an incommensurate reconstruction on Si(111) substrate, while Ge-modified surface shows up as an array of Ge atomic clusters grown on the Cu/Si(111)'pseudo-5 × 5' template. It has been found that C60 fullerenes are highly mobile on the both surfaces, hence at the early growth stages fullerenes are accumulated along the atomic steps forming their quasi-one-dimensional molecular stripes. With further C60 deposition, almost ideal two-dimensional close-packed molecular monolayers are formed. The layers are modulated as evidenced by developing quasi-periodic pattern of dim and bright fullerenes displaying 2 × 2 periodicity. Contrast difference between dim and bright fullerenes is supposed to have a topographical origin, namely, bright fullerenes reside higher than dim fullerenes. Dim fullerenes were concluded to occupy centers of hexagons which constitute honeycomb-like structure of the Cu/Si(111)'pseudo-5 × 5' surface. For the Ge-modified surface, this means that adsorbing C60 fullerenes displace Ge atoms from their original positions to the interstitial sites in the molecular monolayer. Ge atoms were found to terminate rotational motion of selected fullerenes in the layer.

  5. Phonons in A3C60 Lattice and Structural Dynamics

    Directory of Open Access Journals (Sweden)

    Sven Larsson

    2010-01-01

    Full Text Available The critical temperature ( of superconductivity in A3C60 compounds is generally lower smaller with alkali atoms (A. Furthermore decreases with applied pressure. In the BCS model, these trends are explained by the lower density of states at the Fermi level for a decreased lattice constant (R. There is more than one counterexample, however, suggesting that BCS does not give the whole truth. The most important one is that the compound with the largest lattice constant, Cs3C60, is not superconducting at all at ambient pressure. In this paper we derive a novel model where a negative lattice contribution to Hubbard U, proportional to 1/R, is taken into account. It is possible to explain why A3C60 compounds with A = Li, and Na have a low or are not superconducting at all, and why Cs3C60 is superconducting only at applied pressure and then with the highest of all C60 alkali fullerides. It is concluded that the density of states mechanism derived in the BCS model is in doubt. Nevertheless superconductivity in A3C60 depends on electron-phonon coupling. The dominating phonon is the bond stretching Ag phonon, a breathing phonon for the whole fullerene molecular ion.

  6. Formation of clusters composed of C60 molecules via self-assembly in critical fluids

    Science.gov (United States)

    Fukuda, Takahiro; Ishii, Koji; Kurosu, Shunji; Whitby, Raymond; Maekawa, Toru

    2007-04-01

    Fullerenes are promising candidates for intelligent, functional nanomaterials because of their unique mechanical, electronic and chemical properties. However, it is necessary to invent some efficient but relatively simple methods of producing structures composed of fullerenes for the development of nanomechatronic, nanoelectronic and biochemical devices and sensors. In this paper, we show that various structures such as straight fibres, networks formed by fibres, wide sheets and helical structures, which are composed of C60 molecules, are created by placing C60-crystals in critical ethane, carbon dioxide and xenon even though C60 molecules do not dissolve or disperse in the above fluids. It is supposed, judging by the intermolecular potentials between C60 and C60, between C60 and ethane, and between ethane and ethane, that C60-clusters grow with the assistance of solvent molecules, which are trapped between C60 molecules under critical conditions. This room-temperature self-assembly cluster growth process in critical fluids may open up a new methodology of forming structures built up with fullerenes without the need for any ultra-fine processing technologies.

  7. Absorption spectra of C60 and C70 thin films

    Institute of Scientific and Technical Information of China (English)

    周维亚; 解思深; 钱生法; 周棠; 赵日安; 王刚; 钱露茜; 李文治

    1996-01-01

    The spectra of Cm and Cm thin films over a wide energy range (0.6 to 6.5eV) are measured by transmission spectroscopy and photothermal deflection spectroscopy (PDS), and the optical absorption coefficients are obtained. The optical transitions for the Cm and Cw thin films are analyzed according to the molecular orbital model. The weak absorption spectra of the fullerenes are similar to that of amorphous silicon. The optical energy gaps are given by Tauc’s plots as 1.75 and 1.65eV for C60 and C70 thin films, respectively. The disorders in the fullerene films, which resulted in band-tail state or defect state, are indicated by Urbach edge and sub-gap absorption. It is the disorder that brought the difficulty in determination of the energy gap for fullerenes. The effects of the deflection medium and substrate on the weak absorption spectra of fullerene films are also discussed.

  8. Water Soluble Polymers for Pharmaceutical Applications

    Directory of Open Access Journals (Sweden)

    Veeran Gowda Kadajji

    2011-11-01

    Full Text Available Advances in polymer science have led to the development of novel drug delivery systems. Some polymers are obtained from natural resources and then chemically modified for various applications, while others are chemically synthesized and used. A large number of natural and synthetic polymers are available. In the present paper, only water soluble polymers are described. They have been explained in two categories (1 synthetic and (2 natural. Drug polymer conjugates, block copolymers, hydrogels and other water soluble drug polymer complexes have also been explained. The general properties and applications of different water soluble polymers in the formulation of different dosage forms, novel delivery systems and biomedical applications will be discussed.

  9. The nano-science of C60 molecule

    Directory of Open Access Journals (Sweden)

    2002-06-01

    Full Text Available   Over the past few years, nano-science and its associated nano-technology have emerged into prominence in research instiutions across the world. They have brought about new scientific and engineering paradigms, allowing for the manipulation of single atoms and molecules, designing and fabricating new materials, atom-by-atom, and devices that operate on significantly reduced time and length scales. One important area of research in nano-science and nano-technology is carbon-based physics in the form of fullerene physics. The C60 molecule, and other cage-like fullerenes, together with carbon nanotubes provide objects that can be combined to generate three-dimensional functional structures for use in the anticipated nano-technology of future. The unique properties of C60 can also be exploited in designing nano-phase thin films with applications in nanoscopic device technology and processes such as nano-lithography. This requires a deep understanding of the highly complex process of adsorption of this molecule on a variety of substrates. We review the field of nano-scale nucleation and growth of C60 molecules on some of the technologically important substrates. In addition to experimental results, the results of a set of highly accurate computational simulations are also reported.

  10. Network Gold Nanoparticle Aggregates Mediated by C60%以C60为媒介的网状金纳米粒子聚集体的构筑

    Institute of Scientific and Technical Information of China (English)

    李亮; 张衡益; 赵金; 刘育

    2013-01-01

    Metal nanoassemblies have attracted considerable attention in the fields of nanotechnology and biotechnology,due to their unique chemical/optical,electronic and magnetic properties.The "Click chemistry"reaction of permethyl-β-cyclodextrin with porphyrin units led to the formation of a new asymmetric cyclodextrinmodified porphyrin derivative,which was characterized by 1H NMR spectroscopy and electrospray ionization mass spectrometry (ESI-MS).After reaction of the derivative with chloroauric acid,the water-soluble gold nanoparticles(AuNPs) were obtained.The average particle size of AuNPs determined via transmission electron microscopy(TEM) was (5.0±0.8) nm.Then upon interaction with C60,the network aggregates were formed,and their structures were confirmed by UV-Vis absorption spectroscopy and TEM.The results showed that the fullerenes acted as a sort of "molecular glue",leading to the formation of soluble network aggregates,which may provide a new potential application in bioactive nanoscale materials.%通过全甲基化环糊精和卟啉之间的“Click”反应,合成了一种不对称环糊精修饰的卟啉衍生物,并对其结构进行了表征.该化合物与氯金酸作用可以形成平均粒径为5 nm的水溶性金纳米粒子,该金纳米粒子进一步与C60作用形成网状纳米聚集体,并通过紫外光谱和透射电子显微镜验证了聚集体的结构.

  11. High-T C superconductivity in Cs3C60 compounds governed by local Cs-C60 Coulomb interactions

    Science.gov (United States)

    Harshman, Dale R.; Fiory, Anthony T.

    2017-04-01

    Unique among alkali-doped A 3C60 fullerene compounds, the A15 and fcc forms of Cs3C60 exhibit superconducting states varying under hydrostatic pressure with highest transition temperatures at T\\text{C}\\text{meas}   =  38.3 and 35.2 K, respectively. Herein it is argued that these two compounds under pressure represent the optimal materials of the A 3C60 family, and that the C60-associated superconductivity is mediated through Coulombic interactions with charges on the alkalis. A derivation of the interlayer Coulombic pairing model of high-T C superconductivity employing non-planar geometry is introduced, generalizing the picture of two interacting layers to an interaction between charge reservoirs located on the C60 and alkali ions. The optimal transition temperature follows the algebraic expression, T C0  =  (12.474 nm2 K)/ℓζ, where ℓ relates to the mean spacing between interacting surface charges on the C60 and ζ is the average radial distance between the C60 surface and the neighboring Cs ions. Values of T C0 for the measured cation stoichiometries of Cs3-x C60 with x  ≈  0 are found to be 38.19 and 36.88 K for the A15 and fcc forms, respectively, with the dichotomy in transition temperature reflecting the larger ζ and structural disorder in the fcc form. In the A15 form, modeled interacting charges and Coulomb potential e2/ζ are shown to agree quantitatively with findings from nuclear-spin relaxation and mid-infrared optical conductivity. In the fcc form, suppression of T\\text{C}\\text{meas} below T C0 is ascribed to native structural disorder. Phononic effects in conjunction with Coulombic pairing are discussed.

  12. Electronic excitation induced modifications of structural, electrical and optical properties of Cu-C60 nanocomposite thin films

    Science.gov (United States)

    Inani, H.; Singhal, R.; Sharma, P.; Vishnoi, R.; Ojha, S.; Chand, S.; Sharma, G. D.

    2017-09-01

    High energy ion irradiation significantly affects the size and shape of nanoparticles in composites. Low concentration metal fraction embedded in fullerene matrix in form of nanocomposites was synthesized by thermal co-evaporation method. Swift heavy ion irradiation was performed with 120 MeV Au ion beam on Cu-C60 nanocomposites at different fluences 1 × 1012, 3 × 1012, 6 × 1012, 1 × 1013 and 3 × 1013 ions/cm2. Absorption spectra demonstrated that absorption intensity of nanocomposite thin film was increased whereas absorption modes of fullerene C60 were diminished with fluence. Rutherford backscattering spectroscopy was also performed to estimate the thickness of the film and atomic metal fraction in matrix and found to be 45 nm and 3%, respectively. Transmission electron microscopy was performed for structural and particle size evaluation of Cu nanoparticles (NPs) in fullerene C60 matrix. A growth of Cu nanoparticles is observed at a fluence of 3 × 1013 ions/cm2 with a bi-modal distribution in fullerene C60. Structural evolution of fullerene C60 matrix with increasing fluence of 120 MeV Au ion beam is studied by Raman spectroscopy which shows the amorphization of matrix (fullerene C60) at lower fluence. The growth of Cu nanoparticles is explained using the phenomena of Ostwald ripening.

  13. C60(Nd) nanoparticles enhance chemotherapeutic susceptibility of cancer cells by modulation of autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Wei Pengfei; Zhang Li; Man Na; Wen Longping [Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui (China); Lu Yang, E-mail: lpwen@ustc.edu.cn [Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui (China)

    2010-12-10

    Autophagy, an evolutionally conserved intracellular process degrading cytoplasmic proteins and organelles for recycling, has become one of the most remarkable strategies applied in cancer research. The fullerene C60 nanoparticle (nC60) has been shown to induce autophagy and sensitize chemotherapeutic killing of cancer cells, but the details still remain unknown. Here we show that a water-dispersed nanoparticle solution of derivatized fullerene C60, C60(Nd) nanoparticles (nC60(Nd)), has greater potential in inducing autophagy and sensitizing chemotherapeutic killing of both normal and drug-resistant cancer cells than nC60 does in an autophagy-dependent fashion. Additionally we further demonstrated that autophagy induced by nC60/C60(Nd) and Rapamycin had completely different roles in cancer chemotherapy. Our results, for the first time, revealed a novel and more potent derivative of the C60 nanoparticle in enhancing the cytotoxicity of chemotherapeutic agents and reducing drug resistance through autophagy modulation, which may ultimately lead to novel therapeutic strategies in cancer therapy.

  14. C60(Nd) nanoparticles enhance chemotherapeutic susceptibility of cancer cells by modulation of autophagy

    Science.gov (United States)

    Wei, Pengfei; Zhang, Li; Lu, Yang; Man, Na; Wen, Longping

    2010-12-01

    Autophagy, an evolutionally conserved intracellular process degrading cytoplasmic proteins and organelles for recycling, has become one of the most remarkable strategies applied in cancer research. The fullerene C60 nanoparticle (nC60) has been shown to induce autophagy and sensitize chemotherapeutic killing of cancer cells, but the details still remain unknown. Here we show that a water-dispersed nanoparticle solution of derivatized fullerene C60, C60(Nd) nanoparticles (nC60(Nd)), has greater potential in inducing autophagy and sensitizing chemotherapeutic killing of both normal and drug-resistant cancer cells than nC60 does in an autophagy-dependent fashion. Additionally we further demonstrated that autophagy induced by nC60/C60(Nd) and Rapamycin had completely different roles in cancer chemotherapy. Our results, for the first time, revealed a novel and more potent derivative of the C60 nanoparticle in enhancing the cytotoxicity of chemotherapeutic agents and reducing drug resistance through autophagy modulation, which may ultimately lead to novel therapeutic strategies in cancer therapy.

  15. Modelling of C2 addition route to the formation of C60

    CERN Document Server

    Khan, Sabih D

    2016-01-01

    To understand the phenomenon of fullerene growth during its synthesis, an attempt is made to model a minimum energy growth route using a semi-empirical quantum mechanics code. C2 addition leading to C60 was modelled and three main routes, i.e. cyclic ring growth, pentagon and fullerene road, were studied. The growth starts with linear chains and, at n = 10, ring structures begins to dominate. The rings continue to grow and, at some point n > 30, they transform into close-cage fullerenes and the growth is shown to progress by the fullerene road until C60 is formed. The computer simulations predict a transition from a C38 ring to fullerene. Other growth mechanisms could also occur in the energetic environment commonly encountered in fullerene synthesis, but our purpose was to identify a minimal energy route which is the most probable structure. Our results also indicate that, at n = 20, the corannulene structure is energetically more stable than the corresponding fullerene and graphene sheet, however a ring str...

  16. Interstellar Fullerene Compounds and Diffuse Interstellar Bands

    CERN Document Server

    Omont, Alain

    2015-01-01

    Recently, the presence of fullerenes in the interstellar medium (ISM) has been confirmed, especially with the first confirmed identification of two strong diffuse interstellar bands (DIBs) with C60+. This justifies reassesing the importance of interstellar fullerenes of various sizes with endohedral or exohedral inclusions and heterofullerenes (EEHFs). The phenomenology of fullerenes is complex. In addition to formation in shock shattering, fully dehydrogenated PAHs in diffuse interstellar (IS) clouds could perhaps efficiently transform into fullerenes including EEHFs. But it is extremely difficult to assess their expected abundance, composition and size distribution, except for C60+. As often suggested, EEHFs share many properties with C60, as regards stability, formation/destruction, chemical processes and many basic spectral features. We address the importance of various EEHFs as possible DIB carriers. Specifically, we discuss IS properties and the contributions of fullerenes of various sizes and charge su...

  17. Transmutation of fullerenes.

    Science.gov (United States)

    Cross, R James; Saunders, Martin

    2005-03-09

    Fullerenes were pyrolyzed by subliming them into a stream of flowing argon gas and then passing them through an oven heated to approximately 1000 degrees C. C(76), C(78), and C(84) all readily lost carbons to form smaller fullerenes. In the case of C(78), some isomerization was seen. Pyrolysis of (3)He@C(76) showed that all or most of the (3)He was lost during the decomposition. C(60) passes through the apparatus with no decomposition and no loss of helium.

  18. Positively and Negatively Charged Cesium and (C60) m Cs n Cluster Ions.

    Science.gov (United States)

    Renzler, Michael; Kranabetter, Lorenz; Goulart, Marcelo; Scheier, Paul; Echt, Olof

    2017-05-25

    We report on the formation and ionization of cesium and C60Cs clusters in superfluid helium nanodroplets. Size distributions of positively and negatively charged (C60) m Cs n(±) ions have been measured for m ≤ 7, n ≤ 12. Reproducible intensity anomalies are observed in high-resolution mass spectra. For both charge states, (C60) m Cs3(±) and (C60) m Cs5(±) are particularly abundant, with little dependence on the value of m. Distributions of bare cesium cluster ions also indicate enhanced stability of Cs3(±) and Cs5(±), in agreement with theoretical predictions. These findings contrast with earlier reports on highly Cs-doped cationic fullerene aggregates which showed enhanced stability of C60Cs6 building blocks attributed to charge transfer. The dependence of the (C60) m Cs3(-) anion yield on electron energy shows a resonance that, surprisingly, oscillates in strength as m increases from 1 to 6.

  19. Diels-Alder addition to H2O@C60 an electronic and structural study

    Science.gov (United States)

    Reveles, J. Ulises; Govinda, K. C.; Baruah, Tunna; Zope, Rajendra R.

    2017-10-01

    Exohedral reactivity of endohedral fullerenes has aroused a significant interest because of its potential applications. The present letter examines the effect of an entrapped single water molecule on the reactivity of C60. We study the thermodynamics and kinetics of a Diels-Alder reaction occurring at all non-identical bonds of free C60 and H2O@C60. Our calculations show that encapsulation of water does not have a significant effect on H2O@C60 reactivity compared to C60, as attested by the investigation of the reaction under several orientations of H2O inside C60. Reaction and activation energies indicate that [6,6] bonds are the most reactive sites.

  20. C60 as a probe for astrophysical environments

    CERN Document Server

    Brieva, Abel; Jaeger, Cornelia; Huisken, Friedrich; Henning, Thomas

    2016-01-01

    The C60 molecule has been recently detected in a wide range of astrophysical environments through its four active intramolecular vibrational modes (T1u) near 18.9 {\\mu}m, 17.4 {\\mu}m, 8.5 {\\mu}m, and 7.0 {\\mu}m. The strengths of the mid-infrared emission bands have been used to infer astrophysical conditions in the fullerene-rich regions. Widely varying values of the relative intrinsic strengths (RIS) of these four bands are reported in laboratory and theoretical papers, which impedes the derivation of the excitation mechanism of C60 in the astrophysical sources. The spectroscopic analysis of the C60 samples produced with our method delivers highly reproducible RIS values of 100, 25 +- 1, 26 +- 1 and 40 +- 4. A comparison of the inferred C60 emission band strengths with the astrophysical data shows that the observed strengths cannot be explained in terms of fluorescent or thermal emission alone. The large range in the observed 17.4 {\\mu}m/18.9 {\\mu}m emission ratios indicates that either the emission bands co...

  1. Destruction and Resurrection of Atomic Giant resonances in Endohedral Atoms A@C60

    CERN Document Server

    Amusia, M Ya; Chernysheva, L V

    2007-01-01

    It is demonstrated that in photoabsorption by endohedral atoms some atomic Giant resonances are almost completely destroyed while the others are totally preserved due to different action on it of the fullerenes shell. As the first example we discuss the 4d10 Giant resonance in Xe@C60 whereas as the second serves the Giant autoionization resonance in Eu@C60. The qualitative difference comes from the fact that photoelectrons from the 4d Giant resonance has small energies (tens of eV) and are strongly reflected by the C60 fullerenes shell. As to the Eu@C60, Giant autoionization leads to fast photoelectrons (about hundred eV) that go out almost untouched by the C60 shell. As a result of the outgoing electrons energy difference the atomic Giant resonances will be largely destroyed in A@C60 while the Giant autoionization resonance will be almost completely preserved. Thus, on the way from Xe@C60 Giant resonance to Eu@C60 Giant autoionization resonance the oscillation structure should disappear. Similar will be the ...

  2. Collision of low energy Na+ ion with C60

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The collision-induced reaction of Na+ ion with neutral C6o vapour was investigated at the energy range of 10 to 150 eV. The deposited films were studied via laser desorption time-of-flight mass spectroscopy (TOFMS). The fragment products of C60 with even number of carbon atoms, such as Cn+ (n=58, 56, 54), and adduct products, such as Cn+ (n=62, 64, 66, 68) were obser.vcd in the positively charged TOF mass spectra. The endohedral fullerene ion of Na@C60+ was detected when collision energies are above 20 eV. Besides, no negative endohedral fullerene was detected, the products appearing in positively charged mass spectra were also observed in the negatively charged mass spectra. In addition, a series of products with odd number of carbon atoms, such as Cn- (n=53, 55, 57, 59, 61, 63, 65, 67), also appeared, but the intensities of their signals were not as high as that of even numbered. Finally, it is interesting to find that the deposited films are insoluable in toluene, benzene or water. Their Fourier transform infrared (FTIR) spectra seem like those photopolymerized ones. Some of the reaction schemes are proposed to explain the experimental results.

  3. Silver nanoparticles sensitized C60(Ag@C60) as efficient electrocatalysts for hydrazine oxidation: Implication for hydrogen generation reaction

    Science.gov (United States)

    Narwade, Shankar S.; Mulik, Balaji B.; Mali, Shivsharan M.; Sathe, Bhaskar R.

    2017-02-01

    Herein, we report the synthesis of silver nanoparticles (Ag NPs; 10 ± 0.5 nm) sensitized Fullerene (C60; 15 ±2 nm) nanocatalysts (Ag@C60) for the first time showing efficient electroatalytic activity for the oxidation of hydrazine demonstrating activity comparable to that of Pt in acidic, neutral and basic media. The performance is comparable with the best available electrocatalytic system and plays a vital role in the overall hydrogen generation reactions from hydrazine as a one of the fuel cell reaction. The materials are synthesized by a simple and scalable synthetic route involving acid functionalization of C60 followed by chemical reduction of Ag+ ions in ethylene glycol at high temperature. The distributation of Silver nanoparticles (Ag NPs) (morphological information) on C60, bonding, its crystal structure, along with activity towards hydrazine oxidation (electrocatalytic) is studied using TEM, XRD, UV-vis, XPS, FTIR and electrochemical (cyclic voltammetry) studies, respectively. The observed efficient electrocatalytic activity of the as-synthesized electrode is attributed to the co-operative response and associated structural defects due to their oxidative functionalization along with thier cooperative functioning at nanodimensions.

  4. Oxygen-Induced Degradation in C60-Based Organic Solar Cells: Relation Between Film Properties and Device Performance.

    Science.gov (United States)

    Bastos, João P; Voroshazi, Eszter; Fron, Eduard; Brammertz, Guy; Vangerven, Tim; Van der Auweraer, Mark; Poortmans, Jef; Cheyns, David

    2016-04-20

    Fullerene-based molecules are the archetypical electron-accepting materials for organic photovoltaic devices. A detailed knowledge of the degradation mechanisms that occur in C60 layers will aid in the development of more stable organic solar cells. Here, the impact of storage in air on the optical and electrical properties of C60 is studied in thin films and in devices. Atmospheric exposure induces oxygen-trap states that are 0.19 eV below the LUMO of the fullerene C60. Moreover, oxygen causes a 4-fold decrease of the exciton lifetime in C60 layers, resulting in a 40% drop of short-circuit current from optimized planar heterojunction solar cells. The presence of oxygen-trap states increases the saturation current of the device, resulting in a 20% loss of open-circuit voltage. Design guidelines are outlined to improve air stability for fullerene-containing devices.

  5. Uncovering a solvent-controlled preferential growth of buckminsterfullerene (C60) nanowires

    DEFF Research Database (Denmark)

    Geng, Junfeng; Solov'yov, Ilia; Zhou, Wuzong

    2009-01-01

    The fullerene (C_60) nanowires, which possess a highly unusual morphology featured by a prismlike central core and three nanobelt-like wings joined along the growth direction to give an overall Y-shaped cross section, were studied. The experimental observation coupled with theoretical calculation...

  6. UV/Vis spectroscopy of C60 embedded in water ice

    DEFF Research Database (Denmark)

    Cuylle, Steven; Linnartz, Harold; Thrower, John

    2012-01-01

    Electronic solid state spectra are recorded for C60 embedded in 40 K water ice using broad band direct absorption spectroscopy, and assigned with reference to existing matrix data. The results are interesting in view of the recent gas phase detection of fullerenes in the interstellar medium...

  7. Toxicological Effects of Fullerenes on Caenorhabditis elegans

    Science.gov (United States)

    Schomaker, Justin; Snook, Renee; Howell, Carina

    2014-03-01

    The nematode species Caenorhabditis elegans is a useful genetic model organism due to its simplicity and the substantial molecular, genetic, and developmental knowledge about the species. In this study, this species was used to test the toxicological effects of C60 fullerene nanoparticles. In previous studies using rats, a solution of C60 fullerenes in olive oil proved to extend the life of the subjects. The purpose of this experiment was to subject C. elegans to varying concentrations of C60 fullerenes and observe their toxicological effects. Initial findings indicate a link between fullerene exposure and enlargement of the vulva as well as the formation of a small nodule at the base of the tail in some individuals. While the fullerenes are not lethally toxic in C. elegans, results will be presented that pertain to changes in life span and progeny of the nematodes exposed to varying concentrations of fullerenes as well as the mechanisms of toxicity. High magnification imaging via SEM and/or AFM will be used to characterize the fullerene nanoparticles. Testing the toxicity of fullerenes in a wide variety of organisms will lead to a more complete understanding of the effects of fullerenes on living organisms to ultimately understand their effects in humans. This work was supported by National Science Foundation grants DUE-1058829, DMR-0923047, DUE-0806660 and Lock Haven FPDC grants.

  8. Combustion Synthesis of Fullerenes and Fullerenic Nanostructures In Microgravity

    Science.gov (United States)

    Howard, Jack B.; Brooker, John E. (Technical Monitor)

    2002-01-01

    The objectives of the proposed research were to determine the effects of gravity on fullerenes formation in flames and, based on the observed effects, to develop fundamental understanding of fullerenes formation and to identify engineering principles for fullerenes production. The research method consisted of the operation of laminar diffusion flames under normal- and reduced-gravity conditions, and the collection from the flames and subsequent analysis of condensables including any fullerenes present, using coupled high performance liquid chromatography/mass spectrometry and high resolution transmission electron microscopy. The focus included fullerene molecules C60 and C70 and fullerenic nanostructures including tubes, spherules and other shapes. The normal-gravity experiments were performed at MIT and complementary reduced-gravity experiments were to have been contributed by NASA. The independent variables of interest are gravity, fuel type, fuel/oxygen ratio, pressure, gas velocity at burner, diluent type and concentration. Given the large number of variables and the absence of data on either fullerene formation in diffusion flames or gravitational effects on fullerene formation in diffusion or premixed flames, the first part of the work was exploratory while the later part involved detailed study of the most interesting mechanisms. Samples of condensable material from laminar low pressure benzene/argon/oxygen diffusion flames were collected and analyzed by high-performance liquid chromatography to determine the yields of fullerenes, and by high-resolution transmission electron microscopy (HRTEM) to characterize the fullerenic material, i.e., curved-layer nanostructures, on and within the soot particles. The highest concentration of fullerenes was always detected just above the visible stoichiometric surface of a flame. The percentage of fullerenes in the condensable material increases with decreasing pressure. The overall highest amount of fullerenes was found

  9. Water-soluble polymers and compositions thereof

    Science.gov (United States)

    Smith, B.F.; Robison, T.W.; Gohdes, J.W.

    1999-04-06

    Water-soluble polymers including functionalization from the group of amino groups, carboxylic acid groups, phosphonic acid groups, phosphonic ester groups, acylpyrazolone groups, hydroxamic acid groups, aza crown ether groups, oxy crown ethers groups, guanidinium groups, amide groups, ester groups, aminodicarboxylic groups, permethylated polyvinylpyridine groups, permethylated amine groups, mercaptosuccinic acid groups, alkyl thiol groups, and N-alkylthiourea groups are disclosed.

  10. Probing Exciton Diffusion and Dissociation in Single-Walled Carbon Nanotube-C60 Heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Dowgiallo, Anne-Marie; Mistry, Kevin S.; Johnson, Justin C.; Reid, Obadiah G.; Blackburn, Jeffrey L.

    2016-05-19

    The efficiency of thin-film organic photovoltaic (OPV) devices relies heavily upon the transport of excitons to type-II heterojunction interfaces, where there is sufficient driving force for exciton dissociation and ultimately the formation of charge carriers. Semiconducting single-walled carbon nanotubes (SWCNTs) are strong near-infrared absorbers that form type-II heterojunctions with fullerenes such as C60. Although the efficiencies of SWCNT-fullerene OPV devices have climbed over the past few years, questions remain regarding the fundamental factors that currently limit their performance. In this study, we determine the exciton diffusion length in the C60 layer of SWCNT-C60 bilayer active layers using femtosecond transient absorption measurements. We demonstrate that hole transfer from photoexcited C60 molecules to SWCNTs can be tracked by the growth of narrow spectroscopic signatures of holes in the SWCNT 'reporter layer'. In bilayers with thick C60 layers, the SWCNT charge-related signatures display a slow rise over hundreds of picoseconds, reflecting exciton diffusion through the C60 layer to the interface. A model based on exciton diffusion with a Beer-Lambert excitation profile, as well as Monte Carlo simulations, gives the best fit to the data as a function of C60 layer thickness using an exciton diffusion length of approximately 5 nm.

  11. Sorption of nano-C60 clusters in soil: hydrophilic or hydrophobic interactions?

    Science.gov (United States)

    Forouzangohar, Mohsen; Kookana, Rai S

    2011-05-01

    We studied the sorption behaviour of fullerene nano-C(60) particles (nC(60)) in soil from binary solvent mixtures of ethanol-water in order to critically evaluate the previous reports in the literature that the partitioning mechanism explains the soil sorption of fullerene C(60) as hydrophobic molecules. The sorption of nC(60) particles was studied in a range of solvent mixtures by changing volume fractions of ethanol from 20 to 100 percent. Sorption and particle characteristics were found to be very different in ethanol : water mixtures above and below 60% ethanol. In the range of 20-60% ethanol, sorption increased from 1.2 to 14.6 L kg(-1) accompanied by a change in zeta (ζ) potential from -32.4 to -7.2 mV. This observation can be attributed to hydrophilic interactions that negatively charged nC(60) particles undergo with soil colloids and water molecules. From 60% to 100% ethanol volume fractions, hydrophobic interactions of weakly charged nanoparticles may control the overall extent of soil sorption. The findings of this study indicate the importance of hydrophilic forces in controlling the sorption behaviour of nC(60) particles which are stabilized in water dominated solvent mixtures. The validity of the partitioning mechanism and K(OC) modelling approach in describing and estimating the sorption of nC(60) particles in soil (previously suggested in the literature) are, therefore, questioned.

  12. Photocatalytic C60-amorphous TiO2 composites prepared by atomic layer deposition

    Science.gov (United States)

    Justh, Nóra; Firkala, Tamás; László, Krisztina; Lábár, János; Szilágyi, Imre Miklós

    2017-10-01

    Nanocomposites of TiO2 and single fullerene (C60) molecule are prepared by atomic layer deposition (ALD). To create nucleation sites for the ALD reaction, the bare fullerene is functionalized by H2SO4/HNO3 treatment, which results in C60-SO3H. After a NaOH washing step the intermediate hydrolyzes into C60sbnd OH. This process and the consecutive ALD growth of TiO2 are monitored with FTIR, TG/DTA-MS, EDX, Raman, FTIR, XRD, and TEM measurements. Although the TiO2 grown by ALD at 80 and 160 °C onto fullerol is amorphous it enhances the decomposition of methyl orange under UV exposure. This study proves that amorphous TiO2 grown by low temperature ALD has photocatalytic activity, and it can be used e.g. as self-cleaning coatings also on heat sensitive substrates.

  13. Raman Laser Polymerization of C60 Nanowhiskers

    Directory of Open Access Journals (Sweden)

    Ryoei Kato

    2012-01-01

    Full Text Available Photopolymerization of C60 nanowhiskers (C60NWs was investigated by using a Raman spectrometer in air at room temperature, since the polymerized C60NWs are expected to exhibit a high mechanical strength and a thermal stability. Short C60NWs with a mean length of 4.4 μm were synthesized by LLIP method (liquid-liquid interfacial precipitation method. The Ag(2 peak of C60NWs shifted to the lower wavenumbers with increasing the laser beam energy dose, and an energy dose more than about 1520 J/mm2 was found necessary to obtain the photopolymerized C60NWs. However, excessive energy doses at high-power densities increased the sample temperature and lead to the thermal decomposition of polymerized C60 molecules.

  14. Interaction of Human Serum Album and C60 Aggregates in Solution

    Directory of Open Access Journals (Sweden)

    Hailin Wang

    2011-08-01

    Full Text Available An important property of C60 in aquatic ecotoxicology is that it can form stable aggregates with nanoscale dimensions, namely nC60. Aggregation allows fullerenes to remain suspended for a long time, and the reactivity of individual C60 is substantially altered in this aggregate form. Herein, we investigated the interaction of nC60 and human serum album (HSA using the methods of fluorescence, fluorescence dynamics, circular dichroism (CD, and site marker competitive experiments. We proposed a binding model consistent with the available experimental results for the interactions of nC60 with HSA. During the interaction process, the structure and conformation of HSA were affected, leading to functional changes of drug binding sites of HSA.

  15. Photoionization and photofragmentation of the C60+ molecular ion

    Science.gov (United States)

    Baral, K. K.; Aryal, N. B.; Esteves-Macaluso, D. A.; Thomas, C. M.; Hellhund, J.; Lomsadze, R.; Kilcoyne, A. L. D.; Müller, A.; Schippers, S.; Phaneuf, R. A.

    2016-03-01

    Cross-section measurements are reported for single and double photoionization of C60+ ions in the photon energy range 18-150 eV accompanied by the loss of zero to seven pairs of carbon atoms, as well as for fragmentation without ionization resulting in loss of two to eight pairs of C atoms in the photon energy range 18-65 eV. Absolute measurements were performed by merging a beam of C60+ molecular ions with a beam of monochromatized synchrotron radiation. Product channels involving dissociation yielding smaller fullerene fragment ions account for nearly half of the total measured oscillator strength in this energy range. The sum of cross sections for the measured product channels is compared to a published calculation of the total photoabsorption cross section of neutral C60 based on time-dependent density-functional theory. This comparison and an accounting of oscillator strengths indicate that with the exception of C58+, the most important product channels resulting from photoabsorption were accounted for in the experiment. Threshold energies for the successive removal of carbon atom pairs accompanying photoionization are also determined from the measurements.

  16. Coherence of Auger and inter-Coulombic decay processes in the photoionization of Ar@C60 versus Kr@C60

    CERN Document Server

    Magrakvelidze, Maia; Javani, Mohammad H; Madjet, Mohamed E; Manson, Steven T; Chakraborty, Himadri S

    2015-01-01

    For the asymmetric spherical dimer of an endohedrally confined atom and a host fullerene, an innershell vacancy of either system can decay through the continuum of an outer electron hybridized between the systems. Such decays, viewed as coherent superpositions of the single-center Auger and two-center inter-Coulombic (ICD) amplitudes, are found to govern leading decay mechanisms in noble-gas endofullerenes, and are likely omnipresent in this class of nanomolecules. A comparison between resulting autoionizing resonances calculated in the photoionization of Ar@C60 and Kr@C60 exhibits details of the underlying processes.

  17. Decacationic [70]Fullerene Approach for Efficient Photokilling of Infectious Bacteria and Cancer Cells.

    Science.gov (United States)

    Huang, L; Wang, M; Sharma, S K; Sperandio, F F; Maragani, S; Nayka, S; Chang, J; Hamblin, M R; Chiang, L Y

    2013-01-01

    Photodynamic inactivation of pathogenic bacteria and cancer cells by novel water-soluble decacationic fullerene monoadducts, C60[>M(C3N6(+)C3)2] and C70[>M(C3N6(+)C3)2], were investigated. In the presence of a high number of electron-donating iodide anions as parts of quaternary ammonium salts in the arm region, we found that C70[>M(C3N6(+)C3)2] produced more highly reactive HO(•) radical than C60[>M(C3N6(+)C3)2], in addition to singlet oxygen ((1)O2). This finding offers an explanation of the preferential killing of Gram-positive and Gram-negative bacteria by C60[>M(C3N6(+)C3)2] and C70[>M(C3N6(+)C3)2], respectively. The hypothesis is that (1)O2 can diffuse more easily into porous cell walls of Gram-positive bacteria to reach sensitive sites, while the less permeable Gram-negative bacterial cell wall needs the more reactive HO(•) to cause real damage.

  18. Fullerene-Related Nanocarbons and Their Applications

    DEFF Research Database (Denmark)

    Geng, Junfeng; Miyazawa, Kun'ichi; Hu, Zheng;

    2012-01-01

    . From the vast amount of research that has been conducted over the last two decades, it is now apparent that these nanomaterials, notably, carbon nanotubes, carbon-based nanoparticles, graphene, fullerene and fullerene derivatives promise very distinct applications and will add great value to industries......The discovery of fullerene (C60) in 1985 spurred on the subsequent discoveries of a number of fullerene-related novel carbons at the nanometre scale. These nanocarbons are related to one another in structure, providing an interesting spectrum of variants which display an array of unique properties...

  19. Nanoencapsulation of Fullerenes in Organic Structures with Nonpolar Cavities

    Science.gov (United States)

    Murthy, C. N.

    2005-01-01

    The formation of supramolecular structures, assemblies, and arrays held together by weak intermolecular interactions and non-covalent binding mimicking natural processes has been used in applications being anticipated in nanotechnology, biotechnology and the emerging field of nanomedicine. Encapsulation of C60 fullerene by cyclic molecules like cyclodextrins and calixarenes has potential for a number of applications. Similarly, biomolecules like lysozyme also have been shown to encapsulate C60 fullerene. This poster article reports the recent trends and the results obtained in the nanoencapsulation of fullerenes by biomolecules containing nonpolar cavities. Lysozyme was chosen as the model biomolecule and it was observed that there is no covalent bond formed between the bimolecule and the C60 fullerene. This was confirmed from fluorescence energy transfer studies. UV Vis studies further supported this observation that it is possible to selectively remove the C60 fullerene from the nonpolar cavity. This behavior has potential in biomedical applications

  20. C60-PMO: periodic mesoporous buckyballsilica.

    Science.gov (United States)

    Whitnall, Wesley; Cademartiri, Ludovico; Ozin, Geoffrey A

    2007-12-19

    Here we report the first documented synthesis of a periodic mesoporous organosilica (PMO), that contains a multiply bonded C60 moiety integrated into the silica channel walls of the material, dubbed C60-PMO. This is accomplished through the acid-catalyzed co-assembly, of C60(NHCH2CH2CH2Si(OEt)3)x and tetraethylorthosilicate (TEOS) with a polyethyleneoxide-polylpropyleneoxide-polyethyleneoxide triblock copolymer template. The percentage of C60 in the final material was estimated to be a minimum of 63 vol %, but potentially as high as 91 vol %. The effects of the synthesis conditions on the mesostructure of the resulting materials are examined. In particular, we demonstrate that the C60 is uniformly distributed throughout the entire sample by the use of energy dispersive X-ray fluorescence (EDX) analysis and an OsO4 label bonded to the C60.

  1. Biochemical synthesis of water soluble conducting polymers

    Science.gov (United States)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-05-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  2. Biochemical synthesis of water soluble conducting polymers

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Ferdinando F., E-mail: Ferdinando-Bruno@uml.edu [US Army Natick Soldier Research, Development and Engineering Center, Natick, MA 01760 (United States); Bernabei, Manuele [ITAF, Test Flight Centre, Chemistry Dept. Pratica di Mare AFB, 00071 Pomezia (Rome), Italy (UE) (Italy)

    2016-05-18

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  3. Metal (Co, Fe) tribenzotetraazachlorin-fullerene conjugates: impact of direct p-bonding on the redox behaviour and oxygen reduction reaction

    CSIR Research Space (South Africa)

    Ozoemena, KI

    2009-06-01

    Full Text Available Novel hexabutylsulphonyltribenzotetraazachlorin–fullerene (C60) complexes of iron (FeHBSTBTAC–C60) and cobalt (CoHBSTBTAC–C60) have been synthesized and their electrochemistry and oxygen reduction reaction (ORR) compared...

  4. Transmission properties of C60 ions through micro- and nano-capillaries

    Science.gov (United States)

    Tsuchida, Hidetsugu; Majima, Takuya; Tomita, Shigeo; Sasa, Kimikazu; Narumi, Kazumasa; Saitoh, Yuichi; Chiba, Atsuya; Yamada, Keisuke; Hirata, Koichi; Shibata, Hiromi; Itoh, Akio

    2013-11-01

    We apply the capillary beam-focusing method for the C60 fullerene projectiles in the velocity range between 0.14 and 0.2 a.u. We study the C60 transmission properties through two different types of capillaries: (1) borosilicate glass microcapillary with an outlet diameter of 5.5 μm, and (2) Al2O3 multi-capillary foil with a pore size of about 70 nm and a high aspect ratio of about 750. We measured the transmitted particle composition by using the electrostatic deflection method combined with the microchannel plate imaging technique. For the experiments with the single microcapillary, the main transmission component is found to be primary C60 beams that are focused in the area equal to the capillary outlet diameter. Minor components are charge-exchanged C60 ions and charged or neutral fragments (fullerene-like C60-2m and small Cn particles), and their fractions decrease with decreasing the projectile velocity. It is concluded that the C60 transmission fraction is considerably high for both types of the capillaries in the present velocity range.

  5. Semiconductor nanocrystals photosensitize C60 crystals.

    Science.gov (United States)

    Biebersdorf, Andreas; Dietmüller, Roland; Susha, Andrei S; Rogach, Andrey L; Poznyak, Sergey K; Talapin, Dmitri V; Weller, Horst; Klar, Thomas A; Feldmann, Jochen

    2006-07-01

    Semiconductor nanocrystals (SCNCs) made of CdSe, CdTe, and InP are used to photosensitize needlelike C(60) crystals. The photocurrent is increased by up to 3 orders of magnitude as compared with C(60) crystals without SCNCs. The photocurrent spectrum can be tuned precisely by the SCNC size and material, rendering the SCNC-functionalized C(60) crystals an excellent material for spectrally tuneable photodetectors. We explain the increased photocurrent as a result of photoexcited electrons transferring from the SCNCs to the C(60) crystals and causing photoconductivity, while the complementary holes remain trapped in the SCNCs.

  6. The biological mechanisms and physicochemical characteristics responsible for driving fullerene toxicity.

    Science.gov (United States)

    Johnston, Helinor J; Hutchison, Gary R; Christensen, Frans M; Aschberger, Karin; Stone, Vicki

    2010-04-01

    This review provides a comprehensive critical review of the available literature purporting to assess the toxicity of carbon fullerenes. This is required as prior to the widespread utilization and production of fullerenes, it is necessary to consider the implications of exposure for human health. Traditionally, fullerenes are formed from 60 carbon atoms, arranged in a spherical cage-like structure. However, manipulation of surface chemistry and molecular makeup has created a diverse population of fullerenes, which exhibit drastically different behaviors. The cellular processes that underlie observed fullerene toxicity will be discussed and include oxidative, genotoxic, and cytotoxic responses. The antioxidant/cytoprotective properties of fullerenes (and the attributes responsible for driving these phenomena) have been considered and encourage their utilization within the treatment of oxidant-mediated disease. A number of studies have focused on improving the water solubility of fullerenes in order to enable their exploitation within biological systems. Manipulating fullerene water solubility has included the use of surface modifications, solvents, extended stirring, and mechanical processes. However, the ability of these processes to also impact on fullerene toxicity requires assessment, especially when considering the use of solvents, which particularly appear to enhance fullerene toxicity. A number of the discussed investigations were not conducted to reveal if fullerene behavior was due to their nanoparticle dimensions but instead addressed the biocompatibility and toxicity of fullerenes. The hazards to human health, associated with fullerene exposure, are uncertain at this time, and further investigations are required to decipher such effects before an effective risk assessment can be conducted.

  7. Are Biogenic PAHs Precursors for Fullerenes on Earth?

    Science.gov (United States)

    Heymann, D.

    2002-03-01

    C60 fullerene in shungite and in bitumen from the Bohemian Massif could have formed in situ in two steps: 1. Cyclotrimerization of the PAH C20H12. 2. Dehydrogenation of C60H30 to C60. The necessary heat was provided during metamorphism.

  8. Water soluble azido polyisocyanopeptides as functional β-sheet mimics

    NARCIS (Netherlands)

    Schwartz, Erik; Koepf, Matthieu; Kitto, Heather J.; Espelt, Mónica; Nebot-Carda, Vicent J.; Gelder, de Rene; Nolte, Roeland J.M.; Cornelissen, Jeroen J.L.M.; Rowan, Alan E.

    2009-01-01

    The design and synthesis of functional biomimetic water soluble polymers with a defined secondary structure has been developed using β-sheet polyisocyanopeptide scaffolds. Water soluble isocyanopolymers were prepared by random copolymerisation of the azido functionalized isocyanopeptides with nonfun

  9. AM1 Study on Structure and Electronic Properties of the Derivatives of C60-S-TTF

    Institute of Scientific and Technical Information of China (English)

    L(U),Mei-Xiang; XIE,Yan; ZENG,He-Ping

    2004-01-01

    @@ The chemistry of [60]fullerene has been attracted much attention owing to its special structure and unusual property.In recent years, scientists have produced a number of C60-based molecules as well as many materials. Gu et al.[1] have investigated nonlinear optical properties of the derivatives of [60]fullerene, and gained many significant results. The above efforts make photoinduced intra- or inter-molecular electron transfer become currently highly active areas for fundamental study of materials science.

  10. Photophysical Properties and Photoinduced Electron Transfer between[60]Fullerene—containing Cyclic Sulphoxide [C60C60H8SO]and Tetrathiafulvalene(TTF) by Laser Flash Photolysis

    Institute of Scientific and Technical Information of China (English)

    曾和平

    2002-01-01

    Photoinduced electron transfer(PET) processes between C60-C6H8SO and Tetrathiafulvalene(TTF) have been studied by nanosecond laser photolysis.Quantrm yiekds(φet) and rate constants of electron transfer(ket) from TTF to excited triplet state of[60] fullerene-containing cyclic sulphoxide in benzonitrile(BN) have been evaluated by observing the transient absorption bands in the NIR region.With the decay of excited triplet state of [60]fullerene-containing cyclic suplhoxide,the rise of radical anion of [60]fullerene-containing cyclic sulphoxinde is observed.

  11. 15 CFR 8c.60 - Communications.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Communications. 8c.60 Section 8c.60 Commerce and Foreign Trade Office of the Secretary of Commerce ENFORCEMENT OF NONDISCRIMINATION ON THE... Communications. (a) The agency shall take appropriate steps to ensure effective communication with...

  12. 30 years of cosmic fullerenes

    CERN Document Server

    Berne, O; Mulas, G; Joblin, C

    2015-01-01

    In 1985, "During experiments aimed at understanding the mechanisms by which long-chain carbon molecules are formed in interstellar space and circumstellar shells", Harry Kroto and his collaborators serendipitously discovered a new form of carbon: fullerenes. The most emblematic fullerene (i.e. C$_{60}$ "buckminsterfullerene"), contains exactly 60 carbon atoms organized in a cage-like structure similar to a soccer ball. Since their discovery impacted the field of nanotechnologies, Kroto and colleagues received the Nobel prize in 1996. The cage-like structure, common to all fullerene molecules, gives them unique properties, in particular an extraordinary stability. For this reason and since they were discovered in experiments aimed to reproduce conditions in space, fullerenes were sought after by astronomers for over two decades, and it is only recently that they have been firmly identified by spectroscopy, in evolved stars and in the interstellar medium. This identification offers the opportunity to study the ...

  13. On the chemical behavior of C60 hosting H2O and other isoelectronic neutral molecules.

    Science.gov (United States)

    Galano, Annia; Pérez-González, Adriana; del Olmo, Lourdes; Francisco-Marquez, Misaela; León-Carmona, Jorge Rafael

    2014-08-01

    The density functional theory (DFT) was used to investigate the chemical behavior of C60 hosting neutral guest molecules (NGM). The deformed atoms in molecules (DAM) allowed identifying the regions of electron density depletion and accumulation. The studied NGM are CH4, NH3, H2O, and HF. Based on dipole moment and polarizabilities analyses it is predicted that the NGM@C60 should be more soluble in polar solvents than C60. The deformations on the surface electron density of the fullerenes explain this finding, which might be relevant for further applications of these systems. It was found that the intrinsic reactivity of studied NGM@C60 is only moderately higher than that of C60. This trend is supported by the global reactivity indexes and the frontier orbitals analyses. The free radical scavenging activity of the studied systems, via single electron transfer, was found to be strongly dependent on the chemical nature of the reacting free radical. The presence of the studied NGM inside the C60 influences only to some extent the reactivity of C60 toward free radicals. The distortion of the electron density on the C60 cage, caused by the NGM, is directly related to the electron withdrawing capacity of the later.

  14. Spectroscopic studies of the interaction of C 60 and C 70 films with metal substrates

    Science.gov (United States)

    Zhao, Wei; Chen, Li-Quan; Li, Yu-Xin; Zhao, Tie-Nan; Huang, Yu-Zhen; Zhang, Zhan-Xiang; Wang, Hui-Tian; Ye, Pei-Xian; Zhao, Zhong-Xian

    1994-09-01

    The interaction of fullerenes C 60 and C 70 films with metal substrates Au, Ag, In and Sn has been studied by UV-visible absorption spectra, IR, Raman, photoluminescence and second-order nonlinear optics. The absorption spectra show new bands for films on Au, Ag, In and Sn film substrates. For C 60 on Au and Ag, new bands appear, peaking at 723 and 566 nm, respectively. For C 60 film on Sn, several new bands are found at 975.4, 1218, 1557, 2000 and 3570 nm in the NIR and IR regions. Raman spectra reveal an additional peak at 350 cm-1 for C 60 film on Au and five new peaks at 350, 532, 564, 1692 and 1850 cm-1 for the film on Sn. An enhancement of the Raman peak intensity is observed in the latter case. A peak blue shift of photoluminescence band from 749 to 735 nm for C 60 on Sn has also been found. Moreover, a second-order nonlinear optics study at 1.06,μm yields a ten times greater secondary harmonic generation signal intensity for C 60 films on Ag than that of Ag, while no signal is observed for C 60 film on glass. For C 70 on Sn, UV absorption bands broaden and new bands are found at 747, 984 and 1738 nm. The above results suggest a structural distortion of C 60 and C 70 molecules, induced by charge transfer from these metals to the molecules.

  15. Synthesis of Novel Discotic C60-triphenylene Derivative by 1, 3-Dipolar Cycloaddition

    Institute of Scientific and Technical Information of China (English)

    YANG Fa-fu; GUO Hong-yu; XIE Jian-wei; LIU Zhi-qiang; XU Bing-ting

    2012-01-01

    1 IntroductionFullerene has received considerable attention and a great researching interest due to its unique structure and interesting properties[1-3].Many functional groups have been introduced,often region-or stereo-selectively,for tuning the physical properties of C60 and for constructing supramolecular architectures[4-6].Among all kinds of C60 derivatives,the diseotic molecule-substituted C60 derivatives show interesting properties,especially,liquid crystal properties.Up to now,few C60 derivatives with discotic-molecular groups and their liquid crystal properties have been studied.In 1996,Deschenaux et al.[7]reported the first mesomorphic C60-ferrocene derivative.Tian et al.[8]synthesized a C60-perylene derivative in 2004.Nakanishi et al.[9]prepared a series of uncommon liquid C60derivatives with 2,4,6-tris(alkyloxy)benzal groups in 2006.Lately,Geerts et al.[10]described the synthesis of mesogenic phthalocyanine-C60.

  16. ECSTM study of adsorption of C60,C70,C86 and Y@C82 on Au(111)

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The adsorption of a variety of fullerenes (C60,C70,C86,Y@C82) on Au(111) electrode surfaces was comprehensively investigated in 0.1 M HClO4 by electrochemical scanning tunneling microscopy (ECSTM).In the ordered C60’s adlayer,C60 molecules formed either (2(1/3) × 2 3~(1/3))or "in-phase" structure.The high resolution STM image shows that the C60 cage is not simply round but shows a bifurcated feature.The adsorption orientation of C60 on Au(111) is tentatively suggested.In the ordered C70’s adlayer,the perpendicular fullerene molecules are the main adsorption mode and form (2 3~(1/3) × 2 3~(1/3)) structure.However,for C86 and Y@C82,the ordered adlayer could not be obtained on Au(111) under the present condition.These differences may be due to the different molecular shapes and sizes,and the encapsulated metal atom which affects the lattice matches with the substrate.The adsorption of fullerene molecules on Au(111) from disorder to order could be tuned simply by steering the dimensional sizes or shapes of the fullerenes used.

  17. Environmental effects on electron spin relaxation in N@C60

    CERN Document Server

    Morton, J J L; Ardavan, A; Porfyrakis, K; Lyon, S A; Briggs, G A D; Morton, John J. L.; Tyryshkin, Alexei M.; Ardavan, Arzhang; Porfyrakis, Kyriakos

    2006-01-01

    We examine environmental effects of surrounding nuclear spins on the electron spin relaxation of the N@C60 molecule (which consists of a nitrogen atom at the centre of a fullerene cage). Using dilute solutions of N@C60 in regular and deuterated toluene, we observe and model the effect of translational diffusion of nuclear spins of the solvent molecules on the N@C60 electron spin relaxation times. We also study spin relaxation in frozen solutions of N@C60 in CS2, to which small quantities of a glassing agent, S2Cl2 are added. At low temperatures, spin relaxation is caused by spectral diffusion of surrounding nuclear (35,37)Cl spins in the S2Cl2, but nevertheless, at 20 K, T2 times as long as 0.23 ms are observed

  18. Spectromicroscopy of C60 and azafullerene C59N: Identifying surface adsorbed water

    Science.gov (United States)

    Erbahar, Dogan; Susi, Toma; Rocquefelte, Xavier; Bittencourt, Carla; Scardamaglia, Mattia; Blaha, Peter; Guttmann, Peter; Rotas, Georgios; Tagmatarchis, Nikos; Zhu, Xiaohui; Hitchcock, Adam P.; Ewels, Chris P.

    2016-10-01

    C60 fullerene crystals may serve as important catalysts for interstellar organic chemistry. To explore this possibility, the electronic structures of free-standing powders of C60 and (C59N)2 azafullerenes are characterized using X-ray microscopy with near-edge X-ray adsorption fine structure (NEXAFS) spectroscopy, closely coupled with density functional theory (DFT) calculations. This is supported with X-ray photoelectron spectroscopy (XPS) measurements and associated core-level shift DFT calculations. We compare the oxygen 1s spectra from oxygen impurities in C60 and C59N, and calculate a range of possible oxidized and hydroxylated structures and associated formation barriers. These results allow us to propose a model for the oxygen present in these samples, notably the importance of water surface adsorption and possible ice formation. Water adsorption on C60 crystal surfaces may prove important for astrobiological studies of interstellar amino acid formation.

  19. Ground State Reactions of nC60 with Free Chlorine in Water.

    Science.gov (United States)

    Wu, Jiewei; Benoit, Denise; Lee, Seung Soo; Li, Wenlu; Fortner, John D

    2016-01-19

    Facile, photoenhanced transformations of water-stable C60 aggregates (nC60) to oxidized, soluble fullerene derivatives, have been described as key processes in understanding the ultimate environmental fate of fullerene based materials. In contrast, fewer studies have evaluated the aqueous reactivity of nC60 during ground-state conditions (i.e., dark conditions). Herein, this study identifies and characterizes the physicochemical transformations of C60 (as nC60 suspensions) in the presence of free chlorine, a globally used chemical oxidant, in the absence of light under environmentally relevant conditions. Results show that nC60 undergoes significant oxidation in the presence of free chlorine and the oxidation reaction rates increase with free chlorine concentration while being inversely related to solution pH. Product characterization by FTIR, XPS, Raman Spectroscopy, TEM, XRD, TOC, collectively demonstrates that oxidized C60 derivatives are readily formed in the presence of free chlorine with extensive covalent oxygen and even chlorine additions, and behave as soft (or loose) clusters in solution. Aggregation kinetics, as a function of pH and ionic strength/type, show a significant increase in product stabilities for all cases evaluated, even at pH values approaching 1. As expected with increased (surface) oxidation, classic Kow partitioning studies indicate that product clusters are relatively more hydrophilic than parent (reactant) nC60. Taken together, this work highlights the importance of understanding nanomaterial reactivity and the identification of corresponding stable daughter products, which are likely to differ significantly from parent material properties and behaviors.

  20. Model Potentials for a C60 Shell

    CERN Document Server

    Manson, S T; Msezane, A Z

    2016-01-01

    The spatial distribution of electric charges forming a square well potential has been analyzed. It is shown that this potential is created by two concentric spheres with a double layer of charges. A C60 shell potential has been calculated under the assumption that it is formed by the averaged charge density of a neutral atom. It is further demonstrated that the phenomenological potentials simulating the C60 shell potential belong to a family of potentials with a non-flat bottom. Two possible types of C60 model potentials are proposed and their parameters have been calculated. AMS (MOS) Subject Classification. 62P35, 81V55

  1. Electron elastic scattering off $A$@C$_{60}$: The role of atomic polarization under confinement

    CERN Document Server

    Dolmatov, V K; Chernysheva, L V

    2015-01-01

    The present paper explores possible features of electron elastic scattering off endohedral fullerenes $A$@C$_{60}$. It focuses on how dynamical polarization of the encapsulated atom $A$ by an incident electron might alter scattering off $A$@C$_{60}$ compared to the static-atom-$A$ case, as well as how the C$_{60}$ confinement modifies the impact of atomic polarization on electron scattering compared to the free-atom case. The aim is to provide researchers with a "relative frame of reference" for understanding which part of the scattering processes could be due to electron scattering off the encapsulated atom and which due to scattering off the C$_{60}$ cage. To meet the goal, the C$_{60}$ cage is modeled by an attractive spherical potential of a certain inner radius, thickness, and depth which is a model used frequently in a great variety of fullerene studies to date. Then, the Dyson equation for the self-energy part of the Green's function of an incident electron moving in the combined field of an encapsulat...

  2. Energy-level alignment at interfaces between manganese phthalocyanine and C60

    Directory of Open Access Journals (Sweden)

    Daniel Waas

    2017-04-01

    Full Text Available We have used photoelectron spectroscopy to determine the energy-level alignment at organic heterojunctions made of manganese phthalocyanine (MnPc and the fullerene C60. We show that this energy-level alignment depends upon the preparation sequence, which is explained by different molecular orientations. Moreover, our results demonstrate that MnPc/C60 interfaces are hardly suited for application in organic photovoltaic devices, since the energy difference of the two lowest unoccupied molecular orbitals (LUMOs is rather small.

  3. The Curators of the University of Missouri Modeling the Infrared Emission of C_60 in Space

    Science.gov (United States)

    Li, Aigen

    Fullerenes are cage-like molecules of pure carbon, such as C_60, C_70, C_76, and C_84. C_60, also known as buckminsterfullerene, is the most stable fullerene and has a soccer- ball like structure. The presence of fullerenes in space has been suggested and observationally explored since their first synthesis in the laboratory in 1985 by Harry Kroto and his colleagues which earned them the 1996 Nobel prize in chemistry. C_60 (as well as C_70) has recently been detected in reflection nebulae, post-AGB stars, protoplanetary nebulae, planetary nebulae, Herbig Ae/Be stars, and young stellar objects through their characteristic infrared emission bands. The formation of C_60 in interstellar and circumstellar environments is not firmly established. Experimental studies have shown that C_60 can be made by gas-phase condensation (e.g. through vaporization of graphite) in a hydrogen-poor environment. In view of the simultaneous detection of C_60 and PAHs in hydrogen-rich interstellar and circumstellar regions, it has also been suggested that C_60 could be generated by the decomposition of hydrogenated amorphous carbon, or the destruction of PAHs, both induced by shocks and/or UV photoprocessing. The phase (gas or solid) and excitation mechanism of C_60 in interstellar and circumstellar conditions are also hotly debated in the literature. One model suggests that C_60 is attached to dust and emits in solid-phase at the equilibrium temperature of the dust. Another model suggests that C_60 is stochastically excited by UV photons and emits in the gas-phase. We prefer the latter model as in interstellar and circumstellar conditions the energy content of a C_60 molecule is often smaller than the energy of a single starlight photon and C_60 is expected to undergo stochastical heating. We propose a two-year project to model the vibrational excitation of C_60 and calculate its infrared emission spectra in a wide variety of regions (e.g. reflection nebulae excited by stars of a range of

  4. The influence hydrogen atom addition has on charge switching during motion of the metal atom in endohedral Ca@C60H4 isomers.

    Science.gov (United States)

    Raggi, G; Besley, E; Stace, A J

    2016-09-13

    Density functional theory has been applied in a study of charge transfer between an endohedral calcium atom and the fullerene cage in Ca@C60H4 and [Ca@C60H4](+) isomers. Previous calculations on Ca@C60 have shown that the motion of calcium within a fullerene is accompanied by large changes in electron density on the carbon cage. Based on this observation, it has been proposed that a tethered endohedral fullerene might form the bases of a nanoswitch. Through the addition of hydrogen atoms to one hemisphere of the cage it is shown that, when compared with Ca@C60, asymmetric and significantly reduced energy barriers can be generated with respect to motion of the calcium atom. It is proposed that hydrogen atom addition to a fullerene might offer a route for creating a bi-stable nanoswitch that can be fine-tuned through the selection of an appropriate isomer and number of atoms attached to the cage of an endohedral fullerene.This article is part of the themed issue 'Fullerenes: past, present and future, celebrating the 30th anniversary of Buckminster Fullerene'.

  5. Small Molecules in C60 and C70: Which Complexes Could Be Stabilized?

    Science.gov (United States)

    Korona, Tatiana; Dodziuk, Helena

    2011-05-10

    The recent syntheses of complexes involving some small molecules in opened fullerenes and those of hydrogen molecule(s) in C60 and C70 are accompanied in the literature by numerous computations for endohedral fullerene complexes which cope with the problem of the stability of these complexes. In this contribution, stabilization energies of endohedral complexes of C60 and C70 with H2, N2, CO, HCN, H2O, H2S, NH3, CH4, CO2, C2H2, H2CO, and CH3OH guests have been estimated using symmetry-adapted perturbation theory, which, contrary to the standard DFT and some other approaches, correctly describes the dispersion contribution of the host-guest interactions. On the basis of these calculations, the endohedral complexes with all these guests were found stable in the larger fullerene, while the C60 cage was found too small to host the latter four molecules. Except for H2 and H2CO, a stabilization effect for most guests in the C60 cage is about 30 kJ/mol. For H2 and H2O guests, a typical supramolecular effect is observed; namely, the stabilization in the smaller cage is equal to or larger than that in the larger C70 host. Except for the water molecule where the induction interaction plays a non-negligible role, in all complexes the main stabilization effect comes from the dispersion interaction. The information on the stability of hypothetical endohedral fullerene complexes and physical factors contributing to it can be of importance in designing future experiments contributing to their applications.

  6. Obtaining and investigation of C60 semiconductor compounds with a view to create effective solar cells

    Science.gov (United States)

    Elistratova, M. A.; Zakharova, I. B.; Romanov, N. M.

    2015-12-01

    Reproducible vacuum method of thin fullerene films production with Cd impurity on Si, glass and mica surfaces are developed. Thin composite films were obtained by Knudsen cell method. Initial studies of condensation and surface morphology of the films are investigated SEM methods. Optical spectroscopy was used to confirm the obtained results. Results showed the presence of an additional peak associated with the formation of C60-CdTe molecular complexes. SEM results confirm absence of phase separation.

  7. Synthesis and Characterization of Conducting Elastomers Based on Interpenetrated C60-Derived Polymer Networks

    Science.gov (United States)

    2007-11-02

    terpolymers of ethane/propene and 5-vinylnorborn-2-ene (as EPDM ).21 In the latter case, incorporation of the rigid rod-like conducting polymers...electron oxidation of C60 and its analogous, forming the cationic radical intermediates of fullerenes which were stabilized under strong acidic conditions...PTMO chain-softening transition at 14 °C (22.5 J/g) were found to stabilize following the annealing treatment during the first cooling cycle from 200

  8. Electronic structures of the icosahedral C 60H 60 and C 60F 60 molecules

    Science.gov (United States)

    Cioslowski, Jerzy

    1991-06-01

    Electronic structures of the icosahedral C 60H 60 hydrocarbon and its perfluoro analog, C 60F 60, are examined at the HF/4-31G and HF/6-31G** levels. The calculated CC bond lengths are as large as 1.57 Å in C 60H 60 and 1.63 Å in C 60F 60. The bond lengthening is attributed to the HH and FF steric interactions rather than to rehybridization effects. Topological analysis of the electron densities reveals the presence of curve CC bond paths. In addition, FF bond paths are found in C 60F 60 indicating strong non-bonded interaction between the fluorine atoms. The same conclusion is reached from the calculated energy of the isodesmic transfluorination reaction involving the C 2H 6, C 2F 6, C 60H 60, and C 60F 60 molecules.

  9. Inhibition of DNA restrictive endonucleases and Taq DNA polymerase by trimalonic acid C60

    Institute of Scientific and Technical Information of China (English)

    YANG XinLin; CHEN Zhe; MENG XianMei; LI Bo; TAN Xin

    2007-01-01

    Activities of trimalonic acid fullerene (TMA C60) on DNA restrictive enzymatic reaction were investigated by using two restrictive endonucleases Hind III and EcoR I and plasmid pEGFP-N1 with single restrictive site for both enzymes. Meanwhile,TMA C60 was also tested to clarify its effects on polymerase chain reaction (PCR) with the catalyst of Taq DNA polymerase and the template of plasmid pEGFP-N1. The products from restrictive reactions or PCR were detected by agarose gel electrophoresis. It was found that the product amounts from restrictive reactions or PCR decreased significantly with addition of TMA C60. The inhibition by TMA C60 was dose-dependent and IC50 values for reactions of Hind III,EcoR I and PCR were 16.3,6.0 and 6.0 μmol/L,respectively. Addition of two scavengers of reactive oxygen species (ROS),L-ascorbic acid-2-phosphate ester magnesium and sodium azide at the concentrations of 2―10 mmol/L did not antagonize the activities of TMA C60 against PCR and two restrictive reactions. However,increase of Taq DNA polymerase amounts in PCR system antagonized the activities of TMA C60. These data implied that TMA C60 was able to inhibit the activities of the three above-mentioned enzymes involved in DNA metabolism,and that this inhibition probably did not correlate to ROS.

  10. Electron elastic scattering off polarizable $A$@C$_{60}$: The complete study within a particular theory

    CERN Document Server

    Dolmatov, V K; Chernysheva, L V

    2016-01-01

    A deeper insight into electron elastic scattering off endohedral fullerenes $A$@C$_{60}$ is provided. The study accounts for polarization of both the encapsulated atom $A$ and C$_{60}$ cage by an incident electron. It is carried out in the framework of the combination of both a model and the first-principle approximations. A core principle of the model is that the C$_{60}$ cage itself is presented by an attractive spherical potential of a certain inner radius, thickness, and depth. The main idea of the first-principle approximation is that the polarization of $A$@C$_{60}$ by an incident electron is accounted with the help of the Dyson equation for the self-energy part of the Green's function of an incident electron. Calculations are performed for, and comparison is made between the individual cases: (a) when $A$@C$_{60}$ is regarded as a static system, (b) when C$_{60}$ is a static cage, but the encapsulated atom is polarizable, (c) when both C$_{60}$ and $A$ are polarized simultaneously but independently of ...

  11. Program Fullerene

    DEFF Research Database (Denmark)

    Wirz, Lukas; Peter, Schwerdtfeger,; Avery, James Emil

    2013-01-01

    Fullerene (Version 4.4), is a general purpose open-source program that can generate any fullerene isomer, perform topological and graph theoretical analysis, as well as calculate a number of physical and chemical properties. The program creates symmetric planar drawings of the fullerene graph, an......-Fowler, and Brinkmann-Fowler vertex insertions. The program is written in standard Fortran and C++, and can easily be installed on a Linux or UNIX environment....

  12. Fullerene-rare gas mixed plasmas in an electron cyclotron resonance ion source

    CERN Document Server

    Asaji, T; Uchida, T; Minezaki, H; Ishihara, S; Racz, R; Muramatsu, M; Biri, S; Kitagawa, A; Kato, Y; Yoshida, Y

    2015-01-01

    A synthesis technology of endohedral fullerenes such as Fe@C60 has developed with an electron cyclotron resonance (ECR) ion source. The production of N@C60 was reported. However, the yield was quite low, since most fullerene molecules were broken in the ECR plasma. We have adopted gas-mixing techniques in order to cool the plasma and then reduce fullerene dissociation. Mass spectra of ion beams extracted from fullerene-He, Ar or Xe mixed plasmas were observed with a Faraday cup. From the results, the He gas mixing technique is effective against fullerene destruction.

  13. Solubility Characteristics of PCBM and C60.

    Science.gov (United States)

    Boucher, David; Howell, Jason

    2016-11-10

    Empirical data indicate that several good solvents for C60 and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) have substantial polar and hydrogen-bonding components, which are not intrinsic to the structure of the C60 and PCBM molecules themselves. Functional solubility parameter (FSP) and convex solubility parameter (CSP) computations are performed on C60 and PCBM using solubility data available in the literature. The CSP and FSP results are compared to previously reported Hansen solubility parameters (HSPs) and to the parameters calculated using additive functional group contribution methods. The CSP and FSP methods confirm the anomalously large polar and hydrogen-bonding parameters, δP and δH, obtained experimentally for C60 and PCBM. This behavior, which is quite irregular given the structure of the molecules, is due to the fact that several good solvents have high δP and δH values. Thus, these irregularities are highlighted by the CSP and FSP calculations. Additional contradictory solubility characteristics are disclosed by comparing the experimental solubility parameters to a linear solvation energy relationship (LSER) model, additive functional group calculations, and COSMO-RS computations. The FSP solubility function strongly suggests that the solubility parameters do not accurately represent the cohesive energy density properties of C60 and PCBM, as intended, but rather they manifest the properties of the solvents, e.g., high δP and δH values, that are necessary to accommodate these molecules in the liquid phase.

  14. Study of C60/Au(110)-p(6 × 5) Reconstruction from In-Plane X-Ray Diffraction Data

    NARCIS (Netherlands)

    Pedio, M.; Felici, R.; Torrelles, X.; Rudolf, P.; Capozi, M.; Rius, J.; Ferrer, S.

    2000-01-01

    Fullerene molecules absorbed on the highly anisotropic Au(110)-p(1 × 2) surface induce an ordered p(6 × 5) superstructure that has been solved by applying the 2D “direct methods” difference sum function to the surface x-ray diffraction data set. We found that the C60-gold interface is structurally m

  15. Study of C60/Au(110)-p(6 × 5) Reconstruction from In-Plane X-Ray Diffraction Data

    NARCIS (Netherlands)

    Pedio, M.; Felici, R.; Torrelles, X.; Rudolf, P.; Capozi, M.; Rius, J.; Ferrer, S.

    2000-01-01

    Fullerene molecules absorbed on the highly anisotropic Au(110)-p(1 × 2) surface induce an ordered p(6 × 5) superstructure that has been solved by applying the 2D “direct methods” difference sum function to the surface x-ray diffraction data set. We found that the C60-gold interface is structurally m

  16. Theoretical Investigation on Electronic Spectra of Fullerene Polypyridyl Ruthenium(Ⅱ) Complexes by Density Functional Theory%C60-多吡啶Ru(Ⅱ)配合物电子光谱的密度泛函理论研究

    Institute of Scientific and Technical Information of China (English)

    阚玉和; 李强

    2008-01-01

    应用密度泛函理论(DFT)方法对两种C60-多吡啶Ru(Ⅱ)衍生物进行理论研究.在TZP全电子基组优化构型基础上,通过分析前线轨道组成,探讨金属及配体对C60母体影响;以LB及SAOP校正局域密度近似,用含时密度泛函(TDDFT)方法,考虑溶剂化效应,计算化合物1和2的电子吸收光谱.结果表明,化合物1和2在气相与丙酮溶液中所对应的光谱值差异较为明显,溶剂化效应使吸收光谱蓝移.计算得到化合物1和2在丙酮溶液中电子光谱与实验值吻合较好,低能跃迁多为金属参与的混合跃迁,高能跃迁主要由C60与配体部分贡献.

  17. Synthesis of Hyperbranched Polystyrene and Its Fullerene End-capped Derivatives with Multifunctional Atom Transfer Radical Polymerization Initiator%用多官能团引发剂合成超支化聚苯乙烯及其C60衍生物

    Institute of Scientific and Technical Information of China (English)

    杨君炜; 汪长春; 明伟华

    2004-01-01

    通过α-溴丙酰溴与Z5(季戊四醇与2,2-二羟甲基丙酸缩聚的产物)酯化反应制得超支化原子转移自由基聚合(ATRP)引发剂Z5-B(约含19个引发点). 在100 ℃及CuCl/N,N,N',N",N"-五甲基二亚乙基三胺催化下, 用Z5-B引发苯乙烯的ATRP聚合(环己酮为溶剂, 体积分数为50%), 得到超支化的聚苯乙烯, 将溴端基叠氮化后与C60反应, 获得超支化聚苯乙烯C60衍生物. 该超支化C60衍生物可用于光限制材料.

  18. Surface chemical modification of fullerene by mechanochemical treatment

    Science.gov (United States)

    Todorović Marković, B.; Jokanović, V.; Jovanović, S.; Kleut, D.; Dramićanin, M.; Marković, Z.

    2009-06-01

    In this study different encapsulating agents have been used for chemical modification of fullerenes. Fullerenes have reacted with tetrahydrofuran, sodium dodecyl sulfate, sodium dodecylbenzene sulfonate and ethylene vinyl acetate-ethylene vinyl versatate at room temperature under mechanical milling. The obtained powder has been dispersed in water by ultrasonication. The fullerene based colloids have been characterized by UV-vis, FTIR, Raman spectroscopy and atomic force microscopy. FTIR and Raman analysis have shown the presence of C 60 after surface functionalization.

  19. A liquid-crystalline hexa-adduct of [60]fullerene

    OpenAIRE

    Chuard, Thierry; Deschenaux, Robert; Hirsch, Andreas; Schönberger, Hubert

    2006-01-01

    A hexa-adduct of [60]fullerene was synthesized by addition of a mesomorphic twin cyanobiphenyl malonate derivative to C60; whereas the malonate derivative gave a monotropic nematic phase, the fullerene hexa-adduct showed an enantiotropic smectic A phase.

  20. Near-IR Photoluminescence of C60().

    Science.gov (United States)

    Strelnikov, Dmitry V; Kern, Bastian; Kappes, Manfred M

    2017-10-05

    We have observed that C60(+) ions isolated in cryogenic matrices show distinct near-IR photoluminescence upon excitation in the near-IR range. By contrast, UV photoexcitation does not lead to measurable luminescence. Near-IR C60(+) photoluminescence is a one-photon process. The emission is mainly concentrated in one band and corresponds to (2)A1u ← (2)E1g relaxation. We present experimental data for the Stokes shift, power, and temperature dependencies as well as the quantum efficiency of the photoluminescence. Our findings may be relevant for astronomy, considering recent unequivocal assignment of five diffuse interstellar bands to near-IR absorption bands of C60(+).

  1. Efficient Energy Sensitization of C 60 and Application to Organic Photovoltaics

    KAUST Repository

    Trinh, Cong

    2013-08-14

    Fullerenes are currently the most popular electron-acceptor material used in organic photovoltaics (OPVs) due to their superior properties, such as good electron conductivity and efficient charge separation at the donor/acceptor interface. However, low absorptivity in the visible spectral region is a significant drawback of fullerenes. In this study, we have designed a zinc chlorodipyrrin derivative (ZCl) that absorbs strongly in the visible region (450-600 nm) with an optical density 7-fold higher than a C60 film. ZCl efficiently transfers absorbed photoenergy to C60 in mixed films. Application of ZCl as an energy sensitizer in OPV devices leads to an increase in the photocurrent from the acceptor layer, without changing the other device characteristics, i.e., open circuit voltage and fill factor. For example, C 60-based OPVs with and without the sensitizer give 4.03 and 3.05 mA/cm2, respectively, while both have VOC = 0.88 V and FF = 0.44. Our ZCl sensitization approach improves the absorbance of the electron-acceptor layer while still utilizing the beneficial characteristics of C60 in OPVs. © 2013 American Chemical Society.

  2. Morphological phase diagrams of C60 and C70 films on graphite

    Science.gov (United States)

    Sato, Kazuma; Tanaka, Tomoyasu; Akaike, Kouki; Kanai, Kaname

    2017-10-01

    The morphologies of C60 and C70 fullerene films vacuum-deposited onto graphite at various deposition rates and grown at several temperatures were investigated using atomic force microscopy. These fullerene films on graphite are model systems of physisorption of organic molecules that likely exhibit little chemical interaction with the graphite's surface. The morphologies of C60 and C70 films grown on graphite can be understood well from growth models previously reported. Comparison of the morphological phase diagrams obtained for C60 and C70 indicate that the diffusion properties of the adsorbed molecule are key in determining the morphology of the obtained film. The low diffusion rate of C70 resulted in various film morphologies for all deposition conditions tested. Also, the obtained phase diagrams can be understood by the results of fractal dimension analysis on the C60 and C70 islands. The fundamental understanding of film growth obtained using these ideal physisorption systems will aid in understanding film growth by other molecular adsorption systems.

  3. Sublimation of hydrofullerenes C 60H 36 and C 60H 18

    Science.gov (United States)

    Dorozhko, P. A.; Lobach, A. S.; Popov, A. A.; Senyavin, V. M.; Korobov, M. V.

    2001-03-01

    Thermal behavior of two hydrofullerenes, C 60H 36 and C 60H 18, was studied by means of Knudsen cell mass-spectrometry and infrared spectroscopy. Vapor pressures and enthalpies of sublimation at T=550-685 K were measured. Sublimation of the hydrofullerenes was accompanied by partial loss of hydrogen. Decomposition of C 60H 36 was confirmed to be a stepwise process with formation of C 60H 18 as an intermediate product. The material of the Knudsen cell strongly affected the partial pressures and mass-spectra of the hydrofullerene vapor species.

  4. Quantum and classical features of the photoionization spectrum of C$_{60}$

    CERN Document Server

    Verkhovtsev, Alexey V; Solov'yov, Andrey V

    2013-01-01

    Considering the photoionization process of the C$_{60}$ fullerene, we elucidate the contributions of various classical and quantum physics phenomena manifesting themselves in this process. Comparing the results, based on the {\\it ab initio} and model approaches, we map the well-resolved features of the photoionization spectrum to single-particle and collective excitations having the different physical nature. We demonstrate that the peculiarities arising in the photoionization spectrum of C$_{60}$ atop the dominating plasmon excitations have the quantum origin. In particular, we demonstrate that a series of individual peaks can be assigned to the optically allowed discrete transitions, ionization of particular molecular orbitals of the system, or to the single-electron transitions to the continuum. The analysis performed gives a detailed information on the nature of numerous features in the photoionization spectrum of C$_{60}$.

  5. Synthesis of N-acetamide C60 nitride and its performance of optical limiting

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    N-acetamide C60 nitride (N-acetamide-1,2-dihydro-1,2-aza-fullerene[60]) has been synthesized by the reaction of C60 and azidoacetamide and initially characterized. Its mechanism was that the objective product is formed through intermediate triazoline. The computational study shows that N-nitride structure is thermodynamically more stable by using the semi-empirical AM1 SCF-MO method. The properties of optical limiting were tested by using double frequency Nd∶YAG pulse laser system and showed that the optical limiting mechanism is reverse saturation absorption. A wavelength of 532 nm, compared with optical limiting for ns pulse, this new material has good optical limiting character for ps pulse. At wavelength of 707 nm, the capacity of optical limiting of the derivative is prior to C60.

  6. Controlled contact to a C-60 molecule

    DEFF Research Database (Denmark)

    Neel, N.; Kröger, J.; Limot, L.;

    2007-01-01

    The tip of a low-temperature scanning tunneling microscope is approached towards a C-60 molecule adsorbed at a pentagon-hexagon bond on Cu(100) to form a tip-molecule contact. The conductance rapidly increases to approximate to 0.25 conductance quanta in the transition region from tunneling...

  7. HEXAGONAL CLOSE-PACKED C-60

    NARCIS (Netherlands)

    de Boer, Jan; van Smaalen, Sander; Petricek, Vaclav; Dusek, Michal P.; Verheijen, Marcel A.; Meijer, G.

    1994-01-01

    C60 crystals were grown from purified powder material with a multiple sublimation technique. In addition to crystals wit a cubic close-packed (ccp) arrangement, crystals were found with a hexagonal close-packed (hcp) structure. Detailed crystallographic evidence is given, including complete refineme

  8. Controlling the Electronic and Structural Coupling of C60 Nano Films on Fe(001) through Oxygen Adsorption at the Interface.

    Science.gov (United States)

    Picone, Andrea; Giannotti, Dario; Riva, Michele; Calloni, Alberto; Bussetti, Gianlorenzo; Berti, Giulia; Duò, Lamberto; Ciccacci, Franco; Finazzi, Marco; Brambilla, Alberto

    2016-10-05

    C60 molecules coupled to metals form hybrid systems exploited in a broad range of emerging fields, such as nanoelectronics, spintronics, and photovoltaic solar cells. The electronic coupling at the C60/metal interface plays a crucial role in determining the charge and spin transport in C60-based devices; therefore, a detailed understanding of the interface electronic structure is a prerequisite to engineering the device functionalities. Here, we compare the electronic and structural properties of C60 monolayers interfaced with Fe(001) and oxygen-passivated Fe(001)-p(1 × 1)O substrates. By combining scanning tunneling microscopy and spectroscopy, Auger electron spectroscopy, photoemission and inverse photoemission spectroscopies, we are able to elucidate the striking effect of oxygen on the interaction between Fe(001) and C60. Upon C60 deposition on the oxygen-passivated surface, the oxygen layer remains buried at the C60/Fe(001)-p(1 × 1)O interface, efficiently decoupling the fullerene film from the metallic substrate. Tunneling and photoemission spectroscopies reveal the presence of well-defined molecular resonances for the C60/Fe(001)-p(1 × 1)O system, with a large HOMO-LUMO gap of about 3.4 eV. On the other hand, for the C60/Fe(001) interface, a strong hybridization between the substrate states and the C60 orbitals occurs, resulting in broader molecular resonances.

  9. The role of the C2 gas in the emergence of C60 from the condensing carbon vapour

    CERN Document Server

    Ahmad, Shoaib; Tasneem, Afshan

    2016-01-01

    A model has been developed that illustrates the emergence of C60 from the condensing carbon vapor. It is shown to depend upon the decreasing heats of formation for larger cages, exponentially increasing number of isomers for fullerenes that are larger than C60, large cages buckling induced by the pentagon-related protrusions that initiate fragmentation, the structural instability induces fragmentation that shrinks large cages and an evolving gas of C2 that is crucial to the whole process. The model describes a mechanism for the provision and presence of plenty of C2 during the formation and fragmentation processes. The bottom-up formations of large cages followed by the top-down cage shrinkage are shown to be stable, dynamical processes that lead to the C60 dominated fullerene ensemble.

  10. Effects of light energy and reducing agents on C60-mediated photosensitizing reactions.

    Science.gov (United States)

    Quinones, Michael; Zhang, Yazhou; Riascos, Penelope; Hwang, Huey-Min; Aker, Winfred G; He, Xiaojia; Gao, Ruomei

    2014-01-01

    Many biomolecules contain photoactive reducing agents, such as reduced nicotinamide adenine dinucleotide (NADH) and 6-thioguanine (6-TG) incorporated into DNA through drug metabolism. These reducing agents may produce reactive oxygen species under UVA irradiation or act as electron donors in various media. The interactions of C60 fullerenes with biological reductants and light energy, especially via the Type-I electron-transfer mechanism, are not fully understood although these factors are often involved in toxicity assessments. The two reductants employed in this work were NADH for aqueous solutions and 6-TG for organic solvents. Using steady-state photolysis and electrochemical techniques, we showed that under visible light irradiation, the presence of reducing agents enhanced C60 -mediated Type-I reactions that generate superoxide anion (O2(.-)) at the expense of singlet oxygen ((1)O2) production. The quantum yield of O2(.-) production upon visible light irradiation of C60 is estimated below 0.2 in dipolar aprotic media, indicating that the majority of triplet C60 deactivate via Type-II pathway. Upon UVA irradiation, however, both C60 and NADH undergo photochemical reactions to produce O2(.-), which could lead to a possible synergistic toxicity effects. C60 photosensitization via Type-I pathway is not observed in the absence of reducing agents. © 2013 The American Society of Photobiology.

  11. Electronic properties of Mn-phthalocyanine-C60 bulk heterojunctions: Combining photoemission and electron energy-loss spectroscopy

    Science.gov (United States)

    Roth, Friedrich; Herzig, Melanie; Lupulescu, Cosmin; Darlatt, Erik; Gottwald, Alexander; Knupfer, Martin; Eberhardt, Wolfgang

    2015-11-01

    The electronic properties of co-evaporated mixtures (blends) of manganese phthalocyanine and the fullerene C60 (MnPc:C60) have been studied as a function of the concentration of the two constituents using two supplementary electron spectroscopic methods, photoemission spectroscopy (PES) and electron energy-loss spectroscopy (EELS) in transmission. Our PES measurements provide a detailed picture of the electronic structure measured with different excitation energies as well as different mixing ratios between MnPc and C60. Besides a relative energy shift, the occupied electronic states of the two materials remain essentially unchanged. The observed energy level alignment is different compared to that of the related CuPc:C60 bulk heterojunction. Moreover, the results from our EELS investigations show that, despite the rather small interface interaction, the MnPc related electronic excitation spectrum changes significantly by admixing C60 to MnPc thin films.

  12. Toxicity and bioaccumulation of xenobiotic organic compounds in the presence of aqueous suspensions of aggregates of nano-C60

    DEFF Research Database (Denmark)

    Baun, Anders; Sørensen, Sara Nørgaard; Rasmussen, R.F.

    2008-01-01

    The potential of C60-nanoparticles (Buckminster fullerenes) as contaminant carriers in aqueous systems was studied in a series of toxicity tests with algae (Pseudokirchneriella subcapitata) and crustaceans (Daphnia magna). Four common environmental contaminants (atrazine, methyl parathion...... in 4-days-old D. magna was studied with and without addition of C60 in aqueous suspensions. It was found that 85% of the added phenanthrene sorbed to C60-aggregates >200nm whereas about 10% sorption was found for atrazine, methyl parathion, and pentachlorophenol. In algal tests, the presence of C60...... as water phase concentrations. Thus, results from both toxicity tests show that phenanthrene sorbed to C60-aggregates is available for the organisms. For atrazine and methyl parathion no statistically significant differences in toxicities could be observed in algal and daphnid tests as a result...

  13. Water-soluble cavitands - synthesis, solubilities and binding properties

    NARCIS (Netherlands)

    Middel, Oskar; Verboom, Willem; Reinhoudt, David N.

    2002-01-01

    Water-soluble cavitand receptors have been obtained by the introduction of ionizable groups (5, 21-28, 39) and neutral hydrophilic tetraethylene glycol based dendritic wedges (19, 20). The synthesis of these cavitands and a study of their water solubilities and binding properties toward neutral orga

  14. Fullerenes: prospects of using in medicine, biology and ecology

    Directory of Open Access Journals (Sweden)

    D. V. Schur

    2012-02-01

    Full Text Available Results of our own research and academic literature data on the properties of fullerenes and carbon nanotubes are analysed and summarized. Chemical stability of the structure and low toxicity of fullerenes determine their usage in medical chemistry, pharmacology and cosmetology. Due to its mechanical strength the nanotubes have become the basis of clean construction and barrier materials. It is shown that a matrix based on fullerit C60 can be obtained. It allows to store up to 7.7 wt. % hydrogen with formation of hydrofullerit C60H60. The usage of fullerenes for accumulation and storage of hydrogen enhances the prospects of clean hydrogen energy development.

  15. Laser desorption of NO from a thick C 60 film

    Science.gov (United States)

    Hoger, T.; Marzok, C.; Jongma, R. T.; Zacharias, H.

    2006-09-01

    The desorption of NO molecules from a thick C 60 film is reported. A thermal desorption spectrum indicates two adsorption sites with binding energies of Eb = 0.30 eV and 0.55 eV. For laser desorption the fullerene surface is exposed to NO and excited by 7 ns UV laser pulses. Desorbing NO molecules are recorded state selectively as well as time resolved. The time-of-flight measurement indicates three different desorption pathways. A fast channel shows rovibronic temperatures of Trot( v″ = 0) = 370 K, Trot( v″ = 1) = 390 K and Tvib = 610 K as well as strong rotational-translational coupling. The desorption yield for the fast channel increases linearly with pulse energy with a desorption cross section of σ = (5.1 ± 0.9) × 10 -17 cm 2. Dominating the signal for small J″ values is a slow channel with low rotational and translational temperatures of about 110 K. We assign this peak to a laser-induced thermal desorption. For large pump-probe delays the data deviate from the Maxwellian flux distribution and a third channel appears with extremely late arrival times.

  16. Sc20C60: a volleyballene

    Science.gov (United States)

    Wang, Jing; Ma, Hong-Man; Liu, Ying

    2016-06-01

    An exceptionally stable hollow cage containing 20 scandium atoms and 60 carbon atoms has been identified. This Sc20C60 molecular cluster has a Th point group symmetry and a volleyball-like shape that we refer to below as ``Volleyballene''. Electronic structure analysis shows that the formation of delocalized π bonds between Sc atoms and the neighboring pentagonal rings made of carbon atoms is crucial for stabilizing the cage structure. A relatively large HOMO-LUMO gap (~1.4 eV) was found. The results of vibrational frequency analysis and molecular dynamics simulations both demonstrate that this Volleyballene molecule is exceptionally stable.An exceptionally stable hollow cage containing 20 scandium atoms and 60 carbon atoms has been identified. This Sc20C60 molecular cluster has a Th point group symmetry and a volleyball-like shape that we refer to below as ``Volleyballene''. Electronic structure analysis shows that the formation of delocalized π bonds between Sc atoms and the neighboring pentagonal rings made of carbon atoms is crucial for stabilizing the cage structure. A relatively large HOMO-LUMO gap (~1.4 eV) was found. The results of vibrational frequency analysis and molecular dynamics simulations both demonstrate that this Volleyballene molecule is exceptionally stable. Electronic supplementary information (ESI) available: Sc20C60: a Volleyballene_SI. See DOI: 10.1039/c5nr07784b

  17. Superconductivity in alkali-doped fullerene nanowhiskers

    Science.gov (United States)

    Takeya, Hiroyuki; Konno, Toshio; Hirata, Chika; Wakahara, Takatsugu; Miyazawa, Kun'ichi; Yamaguchi, Takahide; Tanaka, Masashi; Takano, Yoshihiko

    2016-09-01

    Superconductivity in alkali metal-doped fullerene nanowhiskers (C60NWs) was observed in K3.3C60NWs, Rb3.0C60NWs and Cs2.0Rb1.0C60NWs with transition temperatures at 17, 25 and 26 K, respectively. Almost full shielding volume fraction (~80%) was observed in K3.3C60NWs when subjected to thermal treatment at 200 °C for a duration of 24 h. In contrast, the shielding fraction of Rb3.0C60NWs and Cs2.0Rb1.0C60NWs were calculated to be 8% and 6%, respectively. Here we report on an extensive investigation of the superconducting properties of these AC60NWs (A  =  K3.3, Rb3.0 and Cs2.0Rb1.0). These properties are compared to the ones reported on the corresponding conventional (single-crystal or powder) K-doped fullerene. We also evaluated the critical current densities of these C60NWs using the Bean model under an applied magnetic field up to 50 kOe.

  18. 5s correlation confinement resonances in Xe-endo-fullerenes

    CERN Document Server

    Dolmatov, V K

    2011-01-01

    Spectacular trends in the modification of the Xe 5s photoionization via interchannel coupling with confinement resonances emerging in the Xe 4d giant resonance upon photoionization of the Xe@C60, Xe@C240 and Xe@C60@C240 endo-fullerenes are theoretically unraveled and interpreted.

  19. Reversible dimerization of C60 molecules in the crystal structure of the bis(arene)chromium fulleride [Cr(C7H8)]2C60.

    Science.gov (United States)

    Hönnerscheid, Andreas; Dinnebier, Robert; Jansen, Martin

    2002-06-01

    Bis(toluene)chromium fulleride, [Cr(C(7)H(8))(2)]C(60), has been synthesized as a black microcrystalline powder from C(60) and [Cr(C(7)H(8))(2)] in toluene. [Cr(C(7)H(8))(2)]C(60) is an ionic compound in which the fullerene is negatively charged and the bis(toluene)chromium molecule positively charged. At T = 250 K a reversible first-order phase transition from a primitive cubic high-temperature phase to a triclinic low-temperature phase occurs. The high-temperature phase [Pm3 macro m, a = 9.9840 (1) A, T = 295 K] is composed of dynamically disordered fulleride anions and bis(toluene)chromium(I) cations in a CsCl-type arrangement. The triclinic low-temperature modification [P1 macro, a = 13.6414 (8), b = 13.8338 (7), c = 13.8548 (7) A, alpha = 91.830 (3), beta = 116.776 (2), gamma = 119.333 (2) degrees, T = 235 K] consists of ordered C(60) dimers and two crystallographically distinct bis(toluene)chromium entities.

  20. The manipulation of C60 in molecular arrays with an STM tip in regimes below the decomposition threshold.

    Science.gov (United States)

    Olyanich, Dmitry A; Kotlyar, Vasily G; Utas, Tatiana V; Zotov, Andrey V; Saranin, Alexander A

    2013-02-08

    The ability of scanning tunneling microscopy to manipulate selected C(60) molecules within close packed C(60) arrays on a (Au,In)/Si(111) surface has been examined for mild conditions below the decomposition threshold. It has been found that knockout of the chosen C(60) molecule (i.e., vacancy formation) and shifting of the C(60) molecule to the neighboring vacant site (if available) can be conducted for wide ranges of bias voltages (from -1.5 to +0.5 V), characteristic manipulation currents (from 0.02 to 100 nA) and powers (from 2 × 10(-8) to 0.1 μW). This result implies that the manipulation is not associated with the electrical effects but rather has a purely mechanical origin. The main requirement for successful C(60) knockout has been found to be to ensure a proper 'impact parameter' (deviation from central impact on the C(60) sphere by the tip apex), which should be less than ~1.5 Å. A certain difference has been detected for the manipulation of C(60) in extended molecular arrays and molecular islands of a limited size. While it is possible to manipulate a single C(60) molecule in an array, in the case of a C(60) island it appears difficult to manipulate a given fullerene without affecting the other ones constituting the island.

  1. X-ray observation of a helium atom and placing a nitrogen atom inside He@C60 and He@C70.

    Science.gov (United States)

    Morinaka, Yuta; Sato, Satoru; Wakamiya, Atsushi; Nikawa, Hidefumi; Mizorogi, Naomi; Tanabe, Fumiyuki; Murata, Michihisa; Komatsu, Koichi; Furukawa, Ko; Kato, Tatsuhisa; Nagase, Shigeru; Akasaka, Takeshi; Murata, Yasujiro

    2013-01-01

    Single crystal X-ray analysis has been used as a powerful method to determine the structure of molecules. However, crystallographic data containing helium has not been reported, owing to the difficulty in embedding helium into crystalline materials. Here we report the X-ray diffraction study of He@C60 and the clear observation of a single helium atom inside C60. In addition, the close packing of a helium atom and a nitrogen atom inside fullerenes is realized using two stepwise insertion techniques, that is, molecular surgery to synthesize the fullerenes encapsulating a helium atom, followed by nitrogen radio-frequency plasma methods to generate the fullerenes encapsulating both helium and nitrogen atoms. Electron spin resonance analysis reveals that the encapsulated helium atom has a small but detectable influence on the electronic properties of the highly reactive nitrogen atom coexisting inside the fullerene, suggesting the potential usage of helium for controlling electronic properties of reactive species.

  2. A search for hydrogenated fullerenes in fullerene-containing planetary nebulae

    CERN Document Server

    Díaz-Luis, J J; Manchado, A; Cataldo, F

    2016-01-01

    Detections of C60 and C70 fullerenes in planetary nebulae (PNe) of the Magellanic Clouds and of our own Galaxy have raised the idea that other forms of carbon such as hydrogenated fullerenes (fulleranes like C60H36 and C60H18), buckyonions, and carbon nanotubes, may be widespread in the Universe. Here we present VLT/ISAAC spectra (R ~600) in the 2.9-4.1 microns spectral region for the Galactic PNe Tc 1 and M 1-20, which have been used to search for fullerene-based molecules in their fullerene-rich circumstellar environments. We report the non-detection of the most intense infrared bands of several fulleranes around ~3.4-3.6 microns in both PNe. We conclude that if fulleranes are present in the fullerene-containing circumstellar environments of these PNe, then they seem to be by far less abundant than C60 and C70. Our non-detections together with the (tentative) fulleranes detection in the proto-PN IRAS 01005+7910 suggest that fulleranes may be formed in the short transition phase between AGB stars and PNe but...

  3. Photoionization of multishell fullerenes studied by ab initio and model approaches

    CERN Document Server

    Verkhovtsev, Alexey; Solov'yov, Andrey V

    2016-01-01

    Photoionization of two buckyonions, C$_{60}$@C$_{240}$ and C$_{20}$@C$_{60}$, is investigated by means of time-dependent density-functional theory (TDDFT). The TDDFT-based photoabsorption spectrum of C$_{60}$@C$_{240}$, calculated in a broad photon energy range, resembles the sum of spectra of the two isolated fullerenes, thus illustrating the absence of strong plasmonic coupling between the fullerenes which was proposed earlier. The calculated spectrum of the smaller buckyonion, C$_{20}$@C$_{60}$, differs significantly from the sum of the cross sections of the individual fullerenes because of strong geometrical distortion of the system. The contribution of collective electron excitations arising in individual fullerenes is evaluated by means of plasmon resonance approximation (PRA). An extension of the PRA formalism is presented, which allows for the study of collective electron excitations in multishell fullerenes under photon impact. An advanced analysis of photoionization of buckyonions, performed using m...

  4. Topochemical 3D polymerization of C60 under high pressure at elevated temperatures.

    Science.gov (United States)

    Yamanaka, Shoji; Kini, Nagesh S; Kubo, Akira; Jida, Saeko; Kuramoto, Hideaki

    2008-04-02

    Fullerene C60 monomer crystals were compressed to a face-centered cubic (fcc) phase with a lattice parameter of a = 11.93(5) A and a micro-Vickers hardness of 4500 kg/mm2 using high-pressure and high-temperature conditions of 15 GPa at 500-600 degrees C. The hardness is compatible with that of cubic boron nitride (c-BN), suggesting the formation of a 3D C60 polymer. The single-crystal X-ray structural analysis revealed that each C60 molecule in the polymer was linked to the 12 nearest neighbors by [2+2] cycloaddition between the common pentagon-hexagon (56) edges. However, ab initio geometry optimization and molecular dynamics calculations suggested that the 3D polymer should have a rhombohedral structure with the space group of R containing [3+3] cycloaddition between the pentagons of C60 molecules within the plane perpendicular to the 3-fold axis. The higher apparent symmetry of fcc was observed as an averaged structure of different orientations of the rhombohedral structure. The R structure can be derived by only a slight rotation of each C60 unit in the (111) plane of the fcc structure. The band-structure calculation suggested that the 3D polymer (R) was a semiconductor; the activation energy for the electrical conductivity was experimentally determined to be 0.25 eV at 550 K.

  5. Rigid rod spaced fullerene as building block for nanoclusters

    Indian Academy of Sciences (India)

    Pallikara K Sudeep; James P Varkey; K George Thomas; Manappurathu V George; Prashant V Kamat

    2003-10-01

    By using phenylacetylene based rigid-rod linkers (PhA), we have successfully synthesized two fullerene derivatives, C60-PhA and C60-PhA-C60. The absorption spectral features of C60, as well as that of the phenylacetylene moiety are retained in the monomeric forms of these fullerene derivatives, ruling out the possibility of any strong interaction between the two chromophores in the ground state. Both the fullerene derivatives form optically transparent clusters, absorbing in the UV-Vis region; this clustering leads to a significant increase in their molar extinction coefficients. TEM characterization of the C60-PhA showed large spherical clusters, with sizes ranging from 150-350 nm, while an elongated wire-type structure was observed for the bisfullerene derivative (C60-PhA-C60). AFM section analysis studies of isolated nanoclusters of C60-PhA-C60, deposited on mica, indicate that smaller clusters associate to form larger nanostructures.

  6. Application of various water soluble polymers in gas hydrate inhibition

    DEFF Research Database (Denmark)

    Kamal, Muhammad Shahzad; Hussein, Ibnelwaleed A.; Sultan, Abdullah S.

    2016-01-01

    . This review presents the various types of water soluble polymers used for hydrate inhibition, including conventional and novel polymeric inhibitors along with their limitations. The review covers the relevant properties of vinyl lactam, amide, dendrimeric, fluorinated, and natural biodegradable polymers...

  7. Which Starch Fraction is Water-Soluble, Amylose or Amylopectin?

    Science.gov (United States)

    Green, Mark M.; And Others

    1975-01-01

    A survey of 22 popular organic chemistry textbooks showed that only four correctly stated that of the two components of starch, amylopectin is the water-soluble, and amylose is the water-insoluble. (MLH)

  8. Deep cavitand receptors with pH-independent water solubility.

    Science.gov (United States)

    Lledó, Agustí; Rebek, Julius

    2010-12-07

    Pendant oligoethyleneglycol groups confer water solubility to a cavitand over a wide pH range. The kinetic stability of the host-guest complexes reveals an effective stabilization through hydrogen bonding even in the highly competitive aqueous environment.

  9. Water-soluble pyrrolopyrrole cyanine (PPCy) NIR fluorophores.

    Science.gov (United States)

    Wiktorowski, Simon; Rosazza, Christelle; Winterhalder, Martin J; Daltrozzo, Ewald; Zumbusch, Andreas

    2014-05-11

    Water-soluble derivatives of pyrrolopyrrole cyanines (PPCys) have been synthesized by a post-synthetic modification route. In highly polar media, these dyes are excellent NIR fluorophores. Labeling experiments show how these novel dyes are internalized into mammalian cells.

  10. Physical and ionic characteristics in water soluble fraction (WSF) of ...

    African Journals Online (AJOL)

    SERVER

    2008-01-04

    Jan 4, 2008 ... Key words: Physical and ionic characteristics, heavy metals, water soluble fraction, crude oil and Azolla africana. ... impact on aquatic life (Camougis, 1981). Water ..... Fish, fisheries, aquatic macrophytes and water quality in.

  11. Water-soluble dopamine-based polymers for photoacoustic imaging

    NARCIS (Netherlands)

    Repenko, T.; Fokong, S.; De Laporte, L.; Go, D.; Kiessling, F.; Lammers, Twan Gerardus Gertudis Maria; Kuehne, A.

    2015-01-01

    Here we present a facile synthetic method yielding a linear form of polydopamine via Kumada-coupling, which can be converted into water-soluble melanin, generating high contrast in photoacoustic imaging.

  12. Plasma concentrations of water-soluble vitamins in metabolic ...

    African Journals Online (AJOL)

    2012-01-21

    Jan 21, 2012 ... levels of water-soluble vitamins with metabolic syndrome and its various components. Aims: This ... thiamine has a role in reducing cellular oxidative stress.[2,12] ... a protective effect on pancreatic beta-cell survival, probably.

  13. Preparation and Preliminary Dielectric Characterization of Structured C60-Thiol-Ene Polymer Nanocomposites Assembled Using the Thiol-Ene Click Reaction

    Directory of Open Access Journals (Sweden)

    Hanaa M. Ahmed

    2015-11-01

    Full Text Available Fullerene-containing materials have the ability to store and release electrical energy. Therefore, fullerenes may ultimately find use in high-voltage equipment devices or as super capacitors for high electric energy storage due to this ease of manipulating their excellent dielectric properties and their high volume resistivity. A series of structured fullerene (C60 polymer nanocomposites were assembled using the thiol-ene click reaction, between alkyl thiols and allyl functionalized C60 derivatives. The resulting high-density C60-urethane-thiol-ene (C60-Thiol-Ene networks possessed excellent mechanical properties. These novel networks were characterized using standard techniques, including infrared spectroscopy (FTIR, differential scanning calorimetry (DSC, dynamic mechanical analysis (DMA, and thermal gravimetric analysis (TGA. The dielectric spectra for the prepared samples were determined over a broad frequency range at room temperature using a broadband dielectric spectrometer and a semiconductor characterization system. The changes in thermo-mechanical and electrical properties of these novel fullerene-thiol-ene composite films were measured as a function of the C60 content, and samples characterized by high dielectric permittivity and low dielectric loss were produced. In this process, variations in chemical composition of the networks were correlated to performance characteristics.

  14. Preparation and Preliminary Dielectric Characterization of Structured C60-Thiol-Ene Polymer Nanocomposites Assembled Using the Thiol-Ene Click Reaction.

    Science.gov (United States)

    Ahmed, Hanaa M; Windham, Amber D; Al-Ejji, Maryam M; Al-Qahtani, Noora H; Hassan, Mohammad K; Mauritz, Kenneth A; Buchanan, Randy K; Buchanan, J Paige

    2015-11-18

    Fullerene-containing materials have the ability to store and release electrical energy. Therefore, fullerenes may ultimately find use in high-voltage equipment devices or as super capacitors for high electric energy storage due to this ease of manipulating their excellent dielectric properties and their high volume resistivity. A series of structured fullerene (C60) polymer nanocomposites were assembled using the thiol-ene click reaction, between alkyl thiols and allyl functionalized C60 derivatives. The resulting high-density C60-urethane-thiol-ene (C60-Thiol-Ene) networks possessed excellent mechanical properties. These novel networks were characterized using standard techniques, including infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermal gravimetric analysis (TGA). The dielectric spectra for the prepared samples were determined over a broad frequency range at room temperature using a broadband dielectric spectrometer and a semiconductor characterization system. The changes in thermo-mechanical and electrical properties of these novel fullerene-thiol-ene composite films were measured as a function of the C60 content, and samples characterized by high dielectric permittivity and low dielectric loss were produced. In this process, variations in chemical composition of the networks were correlated to performance characteristics.

  15. Enhanced Fullerene Yield in Plasma-Aerosol Reactor at Cryogenic Boundary Temperature

    CERN Document Server

    Jouravlev, Mikhail

    2011-01-01

    We demonstrate remarkably enhanced yield of C60 fullerenes in an aerosol discharge chamber due to the additional presence of a strong spatial temperature gradient. The role of the temperature gradients in the increased yield of C60 and fullerene-like structures is discussed. The reaction is not fully reversible and carbon soot matter is formed as a secondary product in the form of carbon aerosol particles. The increasing concentration of C60 was easily recognized from the characteristic UV-spectra. The result of this paper will be useful for improvement of fullerene synthesis technology and for application to constructing new types of aerosol-plasma reactors.

  16. Structure property relationships for the nonlinear optical response of fullerenes

    Science.gov (United States)

    Rustagi, Kailash C.; Ramaniah, Lavanya M.; Nair, Selvakumar V.

    1994-11-01

    We present a phenomenological theory of nonlinear optical response of fullerenes. An empirical tight-binding model is used in conjunction with a classical electromagnetic picture for the screening. Since in bulk media such a picture of screening corresponds to the self- consistent field approach, the only additional approximation involved in our approach is the neglect of nonlocality. We obtain reliable estimates for the linear and nonlinear susceptibilities of C60, C70, C76 and other pure carbon fullerenes and also substituted fullerenes. The relatively large values of (beta) that we obtain for C76 and substituted fullerenes appear promising for the development of fullerene-based nonlinear optical materials. Our phenomenological picture of screening provides a good understanding of the linear absorption spectra of higher fullerenes and predicts that a comparison of the one-photon and multi-photon spectra will provide an insight into screening effects in these systems.

  17. Degradability of aged aquatic suspensions of C60 nanoparticles

    DEFF Research Database (Denmark)

    Hartmann, Nanna Isabella Bloch; Buendia, Inmaculada M.; Bak, Jimmy

    2011-01-01

    In this study, aged aqueous suspensions of C(60) (nC(60)) were investigated in the respirometric OECD test for ready biodegradability. Two suspensions of nC(60) were prepared by stirring and aged under indirect exposure to sunlight for 36 months. ATR-FTIR analyses confirmed the presence of C(60...

  18. Superconductivity at 40K in Cesium Doped C60

    NARCIS (Netherlands)

    Palstra, T.T.M.; Zhou, O.; Iwasa, Y.; Sulewski, P.E.; Fleming, R.M.; Zegarski, B.R.

    1995-01-01

    We report superconductivity in Cs3C60 at 40K using ac susceptibility measurements under hydrostatic conditions up to 15 kbar. Cs3C60 was prepared by reaction of C60 with Cs in liquid ammonia, followed by heating at 150°C. This route circumvents formation of the energetically more stable Cs1C60 and C

  19. On the fluorescence of C60 at room temperature

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The fluorescence properties of C 60 in different organic solvents have been investigated at room temperature. Three fluorescence emission centers are discovered and ascribed to different aggregations of C 60 in solvent. A series of blue fluorescence peaks centered at 440 nm derive from C 60 nanoparticles; a distinctive yellow-green fluorescence band in 575 nm region arises from the aggregates of C 60 nanoparticles; a more informative salmon fluorescence band around 700 nm originates from C 60 microcrystals. And the distinct configurations of C 60 aggregations are closely associated with the characteristic interaction between C 60 and solvent molecules.

  20. Novel facile method for obtaining CdSe/polyaniline/C60 composite materials

    Science.gov (United States)

    Rusen, Edina; Diacon, Aurel; Mocanu, Alexandra; Nistor, Leona Cristina

    2016-08-01

    This study presents a novel method for the oxidative polymerization of aniline (ANI) by employing fullerene C60/cadmium selenide (CdSe) quantum dots, as promoting agent of the polymerization system. The polymerization initiation mechanism is based on the difference between the HOMO-LUMO energy levels of the components which permits the formation of a continuous donor-acceptor exchange. Both the polymerization reaction evolution and the molecular weights of the obtained polymers have been characterized. The novelty of the paper consists in the synthesis of a novel nano-composite material through a novel polymerization technique. The resulting material containing PANI, CdSe quantum dots and C60 has been characterized by UV-Vis, NIR, fluorescence, TEM and GPC analyses.

  1. Effect of doping of N and B atoms on thermoelectric properties of C60 molecule

    Indian Academy of Sciences (India)

    Mojtaba Yaghobi; Fazel Ardeshir Larijani

    2015-01-01

    In this work, the doping effect on the thermoelectric properties of the C60 molecule (fullerene) was studied by considering inelastic electron–phonon interactions. It is seen that the maximum value of thermal conductance (max) with respect to the molecules are max(C59N) < max(C60) < max(C59B). Also, the oscillatory behaviour of thermal conductance is dramatically dependent on the type of molecules. The values of figure of merit (ZT) against energy and with respect to the type of molecules are between 0.25 × 10−5 and 0.194 × 10−3 and effect of the type of molecules is small on the minimum value of ZT.

  2. Novel facile method for obtaining CdSe/polyaniline/C60 composite materials.

    Science.gov (United States)

    Rusen, Edina; Diacon, Aurel; Mocanu, Alexandra; Nistor, Leona Cristina

    2016-08-30

    This study presents a novel method for the oxidative polymerization of aniline (ANI) by employing fullerene C60/cadmium selenide (CdSe) quantum dots, as promoting agent of the polymerization system. The polymerization initiation mechanism is based on the difference between the HOMO-LUMO energy levels of the components which permits the formation of a continuous donor-acceptor exchange. Both the polymerization reaction evolution and the molecular weights of the obtained polymers have been characterized. The novelty of the paper consists in the synthesis of a novel nano-composite material through a novel polymerization technique. The resulting material containing PANI, CdSe quantum dots and C60 has been characterized by UV-Vis, NIR, fluorescence, TEM and GPC analyses.

  3. Novel facile method for obtaining CdSe/polyaniline/C60 composite materials

    Science.gov (United States)

    Rusen, Edina; Diacon, Aurel; Mocanu, Alexandra; Nistor, Leona Cristina

    2016-01-01

    This study presents a novel method for the oxidative polymerization of aniline (ANI) by employing fullerene C60/cadmium selenide (CdSe) quantum dots, as promoting agent of the polymerization system. The polymerization initiation mechanism is based on the difference between the HOMO-LUMO energy levels of the components which permits the formation of a continuous donor-acceptor exchange. Both the polymerization reaction evolution and the molecular weights of the obtained polymers have been characterized. The novelty of the paper consists in the synthesis of a novel nano-composite material through a novel polymerization technique. The resulting material containing PANI, CdSe quantum dots and C60 has been characterized by UV-Vis, NIR, fluorescence, TEM and GPC analyses. PMID:27572228

  4. Ultrafast dynamics and fragmentation of C60 in intense laser pulses

    CERN Document Server

    Lin, Zheng-Zhe

    2014-01-01

    The radiation-induced fragmentation of the C60 fullerene was investigated by the tight-binding electron-ion dynamics simulations. In intense laser field, the breathing vibrational mode is much more strongly excited than the pentagonal-pinch mode. The fragmentation effect was found more remarkable at long wavelength lambda>800 nm rather than the resonant wavelengths due to the internal laser-induced dipole force, and the production ratio of C and C2 rapidly grows with increasing wavelength. By such fragmentation law, C atoms, C2 dimers or large Cn fragments could be selectively obtained by changing the laser wavelength. And the fragmentation of C60 by two laser pulses like the multi-step atomic photoionization was investigated.

  5. Polymer fullerene solution phase behaviour and film formation pathways.

    Science.gov (United States)

    Dattani, Rajeev; Cabral, João T

    2015-04-28

    We report the phase behaviour of polymer/fullerene/solvent ternary mixtures and its consequence for the morphology of the resulting composite thin films. We focus particularly on solutions of polystyrene (PS), C60 fullerene and toluene, which are examined by static and dynamic light scattering, and films obtained from various solution ages and thermal annealing conditions, using atomic force and light microscopy. Unexpectedly, the solution phase behaviour below the polymer overlap concentration, c*, is found to be described by a simple excluded volume argument (occupied by the polymer chains) and the neat C60/solvent miscibility. Scaling consistent with full exclusion is found when the miscibility of the fullerene in the solvent is much lower than that of the polymer, giving way to partial exclusion with more soluble fullerenes (phenyl-C61-butyric acid methyl ester, PCBM) and a less asymmetric solvent (chlorobenzene), employed in photovoltaic devices. Spun cast and drop cast films were prepared from PS/C60/toluene solutions across the phase diagram to yield an identical PS/C60 composition and film thickness, resulting in qualitatively different morphologies in agreement with our measured solution phase boundaries. Our findings are relevant to the solution processing of polymer/fullerene composites (including organic photovoltaic devices), which generally require effective solubilisation of fullerene derivatives and polymer pairs in this concentration range, and the design of well-defined thin film morphologies.

  6. Effect of the structure distortion on the high photocatalytic performance of C60/g-C3N4 composite

    Science.gov (United States)

    Ma, Xiaojuan; Li, Xinru; Li, Mengmeng; Ma, Xiangchao; Yu, Lin; Dai, Ying

    2017-08-01

    C60/g-C3N4 composite was reported experimentally to be of high photocatalytic activity in degrading organics. To investigate the underlying mechanism of high photocatalytic performance, the structural and electronic properties of g-C3N4 monolayers with adsorbing and removing fullerene C60 are studied by means of density functional theory calculations. After 25 possible configurations examination, it is found that C60 prefers to stay upon the ;junction nitrogen; with the carbon atom of fullerene being nearest to monolayers. Correspondingly, a type-I band alignment appears. Our results further demonstrate that the adsorption of C60 can lead to an irreversible structure distortion for g-C3N4 from flat to wrinkle, which plays a crucial role in improving photocatalytic performance other than the separation of carriers at interface due to the formation of type-II heterojunctions as previous report. Compared to flat one, the light absorption of wrinkled structure shows augmented, the valence band maximum shifts towards lower position along with a stronger photo-oxidation capability. Interestingly, the results indicate that the energy, light absorption and band edge all have a particular relationship with wrinkle degree. The work presented here can be helpful to understand the mechanism behind the better photocatalytic performance for C60 modified g-C3N4.

  7. Synthesis of mesogenic phthalocyanine-C60 donor–acceptor dyads designed for molecular heterojunction photovoltaic devices

    Directory of Open Access Journals (Sweden)

    Yves Henri Geerts

    2009-10-01

    Full Text Available A series of phthalocyanine-C60 dyads 2a–d was synthesized. Key steps in their synthesis are preparation of the low symmetry phthalocyanine intermediate by the statistical condensation of two phthalonitriles, and the final esterification of the fullerene derivative bearing a free COOH group. Structural characterization of the molecules in solution was performed by NMR spectroscopy, UV–vis spectroscopy and cyclic voltammetry. Preliminary studies suggest formation of liquid crystalline (LC mesophases for some of the prepared dyads. To the best of our knowledge, this is the first example of LC phthalocyanine-C60 dyads.

  8. Improved photovoltaic performance of heterostructured tetrapod-shaped CdSe/CdTe nanocrystals using C60 interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanqin; Mastria, Rosanna; Fiore, Angela; Nobile, Concetta; Yin, Lunxiang; Cheng, Gang; Cingolani, Roberto; Manna, Liberato; Gigli, Giuseppe [National Nanotechnology Lab of CNR-INFM (NNL), University of Salento, Lecce (Italy); Biasiucci, Mariano [National Nanotechnology Lab of CNR-INFM (NNL), University of Salento, Lecce (Italy); Physical Department, University of Salerno, Baronissi (Italy); Cucolo, Anna Maria [Physical Department, University of Salerno, Baronissi (Italy)

    2009-11-26

    Photovoltaic (PV) devices based on CdSe/CdTe-C60 active layers, in which the nanocrystal and fullerene (C60) layers work as electron-donor and electron-acceptor/transport layers, respectively, were fabricated. Efficiencies up to 0.62% were reached in the hybrid cells. The PV performance was greatly improved with respect to that of CdSe/CdTe-P3HT- and CdSe/CdTe-based devices, fabricated as reference. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  9. New type of redox nanoprobe: C60-based nanomaterial and its application in electrochemical immunoassay for doping detection.

    Science.gov (United States)

    Han, Jing; Zhuo, Ying; Chai, Ya-Qin; Xiang, Yun; Yuan, Ruo

    2015-02-03

    Carbon nanomaterials were usually exploited as nanocarriers in an electrochemical immunosensor but rarely acted as redox nanoprobes. Herein, our motivation is to adequately utilize the inner redox activity of fullerene (C60) to obtain a new type of redox nanoprobe based on a hydrophilic C60 nanomaterial. First, C60 nanoparticles (C60NPs) were prepared by phase-transfer method and functionalized with amino-terminated polyamidoamine (PAMAM) to obtain the PAMAM decorated C60NPs (PAMAM-C60NPs) which have better hydrophilicity compared to that of unmodified C60NPs and possesses abundant amine groups for further modification. Following that, gold nanoparticles (nano-Au) were absorbed on the PAMAM-C60NPs surface, and the resultant Au-PAMAM-C60NPs were employed as a new type of redox nanoprobe and nanocarrier to label detection antibodies (Ab2). Doping control has become the biggest problem facing international sport. Erythropoietin (EPO) as a blood doping agent has been a hotspot in doping control. After sandwich-type immunoreaction between EPO (as a model) and Ab2-labeled Au-PAMAM-C60NPs, the resultant immunosensor was further incubated with a drop of tetraoctylammonium bromide (TOAB) which acts as booster to arouse the inner redox activity of Au-PAMAM-C60NPs, thus a pair of reversible redox peaks is observed. As a result, the proposed immunosensor shows a wide linear range and a relatively low detection limit for EPO. This strategy paves a new avenue for exploring the redox nanoprobe based on carbon nanomaterials in the electrochemical biosensor field.

  10. Asymmetric Flow Field Flow Fractionation of Aqueous C60 Nanoparticles with Size Determination by Dynamic Light Scattering and Quantification by Liquid Chromatography Atmospheric Pressure Photo-Ionization Mass Spectrometry

    Science.gov (United States)

    A size separation method was developed for aqueous C60 fullerene aggregates (aqu/C60) using asymmetric flow field flow fractionation (AF4) coupled to a dynamic light scattering detector in flow through mode. Surfactants, which are commonly used in AF4, were avoided as they may al...

  11. Immunostimulatory properties and enhanced TNF- α mediated cellular immunity for tumor therapy by C60(OH)20 nanoparticles

    Science.gov (United States)

    Liu, Ying; Jiao, Fang; Qiu, Yang; Li, Wei; Qu, Ying; Tian, Chixia; Li, Yufeng; Bai, Ru; Lao, Fang; Zhao, Yuliang; Chai, Zhifang; Chen, Chunying

    2009-10-01

    Publications concerning the mechanism of biological activity, especially the immunological mechanism of C60(OH)20 nanoparticles, are relatively limited. However, the structure and characteristics of this carbon allotrope have been widely investigated. In this paper, we have demonstrated that water-soluble C60(OH)20 nanoparticles have an efficient anti-tumor activity in vivo, and show specific immunomodulatory effects to the immune cells, such as T cells and macrophages, both in vivo and in vitro. For example, C60(OH)20 nanoparticles can increase the production of T-helper cell type 1 (Th1) cytokines (IL-2, IFN- γ and TNF-α), and decrease the production of Th2 cytokines (IL-4, IL-5 and IL-6) in serum samples. On the other hand, C60(OH)20 nanoparticles show almost no adverse effect to the viability of immune cells in vitro but stimulate the immune cells to release more cytokines, in particular TNF- α, which plays a key role in the cellular immune process to help eliminate abnormal cells. TNF- α production increased almost three-fold in treated T lymphocytes and macrophages. Accordingly, we conclude that C60(OH)20 nanoparticles have an efficient anti-tumor activity and this effect is associated with an increased CD4+/CD8+ lymphocyte ratio and the enhancement of TNF- α production. The data suggest that C60(OH)20 nanoparticles can improve the immune response to help to scavenge and kill tumor cells.

  12. A First Principle Comparative Study on Chemisorption of H2 on C60, C80, and Sc3N@C80 in Gas Phase and Chemisorption of H2 on Solid Phase C60

    Directory of Open Access Journals (Sweden)

    Hongtao Wang

    2014-01-01

    Full Text Available The chemisorptions of H2 on fullerenes C60 and C80, endofullerene Sc3C@C80 and solid C60 were comparatively studied. A chain reaction mechanism for dissociative adsorption of H2 on solid C60 is proposed under high pressure. The breaking of H–H bond is concerted with the formation of two C–H bonds on two adjacent C60 in solid phase. The adsorption process is facilitated by the application of high pressure. The initial H2 adsorption on two adjacent C60 gives a much lower barrier 1.36 eV in comparison with the barrier of adsorption on a single C60 (about 3.0 eV. As the stereo conjugate aromaticity of C60 is destructed by the initial adsorption, some active sites are created. Hence the successive adsorption becomes easier with much low barriers (0.6 eV. In addition, further adsorption can create new active sites for the next adsorption. Thus, a chain reaction path is formed with the initial adsorption dominating the whole adsorption process.

  13. Low-temperature scanning tunneling microscopy/ultraviolet photoelectron spectroscopy investigation of two-dimensional crystallization of C60: pentacence binary system on Ag(111)

    Science.gov (United States)

    Lin Zhang, Jia; Hong Liang Zhang, Kelvin; Qiang Zhong, Jian; Chao Niu, Tian; Chen, Wei

    2012-02-01

    Atomic scale investigation of temperature-dependent two-dimensional (2 D) crystallization processes of fullerene-C60 on pentacene-covered Ag(111) surface has been carried out by in situ low-temperature scanning tunneling microscopy (LT-STM) experiments. To evaluate the effect of molecule-substrate interfacial interactions on the 2 D crystallization of C60: pentacene binary system, we also carried out the same self-assembly experiments of C60 on monolayer pentacene covered graphite substrate. It is revealed that temperature-dependent structural transition of various ordered C60 nanoassemblies is strongly influenced by the molecule-Ag(111) interfacial interactions, and further mediated by the weak C60-pentacene intermolecular interactions. In situ ultraviolet photoelectron spectroscopy (UPS) has been used to evaluate the nature of the intermolecular interactions between C60 and pentacene films.

  14. Magnetic field effect spectroscopy of C60-based films and devices

    Science.gov (United States)

    Gautam, Bhoj R.; Nguyen, Tho D.; Ehrenfreund, Eitan; Vardeny, Z. Valy

    2013-04-01

    We performed spectroscopy of the magnetic field effect (MFE) including magneto-photoinduced absorption (MPA) and magneto-photoluminescence (MPL) at steady state conditions in annealed and pristine fullerene C60 thin films, as well as magneto-conductance (MC) in organic diodes based on C60 interlayer. The hyperfine interaction has been shown to be the primary spin mixing mechanism for the MFE in the organics. In this respect, C60 is a unique material because 98.9% of the carbon atoms are 12C isotope, having spinless nucleus and thus lack hyperfine interaction. In spite of this, we obtained substantial MPA (up to ˜15%) and significant MC and MPL in C60 films and devices, and thus mechanisms other than the hyperfine interaction are responsible for the MFE in this material. Specifically, we found that the MFE(B) response is composed of narrow (˜10 mT) and broad (>100 mT) components. The narrow MFE(B) component is due to spin-dependent triplet exciton recombination in C60, which dominates the MPA(B) response at low pump intensities in films, or the MC response at small current densities in devices. In contrast, the broad MFE(B) component dominates the MPA(B) response at high pump intensities (or large current densities for MC(B)) and is attributed to spin mixing in the polaron pairs spin manifold due to g-factor mismatch between the electron- and hole-polarons in C60. Our results show that the organic MFE has a much broader scope than believed before.

  15. Characterization of naturally-occurring and modified fullerenes by Fourier transform mass spectrometry

    Science.gov (United States)

    Hettich, Robert L.; Jin, Changming; Compton, Robert N.; Buseck, Peter R.; Tsipursky, Semeon J.

    1993-10-01

    Fourier transform mass spectrometry (FTMS) employing both laser desorption/ionization and thermal desorption/electron ionization is useful for the detection and structural characterization of fullerenes and chemically-modified fullerenes. Examination of a carbon-rich shungite rock sample from Russia by transmission electron microscopy and FTMS provided evidence of naturally-occurring fullerenes. Ion-molecule reactions can be studied with FTMS to investigate the electron affinities of modified fullerenes. By monitoring charge exchange reactions, the electron affinities of C60Fx (x=44,46) and C70Fy (y=52,54) were found to be substantially higher than the values for the parent fullerenes.

  16. Synthesis of gold nano-wire and nano-dumbbell shaped colloids and AuC60 nano-clusters

    Science.gov (United States)

    Landon, Preston B.; Jarvis, Brandon C.; Gilleland, Cody L.; Renfro, Tim; Gutierrez, Jose; Synowczynski, Jennifer; Hirsch, Samuel G.; Glosser, Robert

    2005-08-01

    A technique for the fabrication of colloidal gold nano-wire and nano-dumbbell shaped particles using carbon nanotubes and rod shaped viruses as templates is described. The gold (Au) encapsulation process was accomplished by the precipitation of gold chloride from aqueous solutions. When this process was conducted in the presence of hydroxylated C60, small pieces of phase-separated composites of AuC60 appeared to have formed. These nano-clusters may turn out to be large noble metal analogs of the alkali metal fullerides with the smallest geometrically possible Au aggregate consisting of 55 gold atoms. The existence of noble metal fullerene composites has been previously theorized. The alkali metal fullerides are examples of phase separated solids and have exhibited superconductivity with temperatures as high 33K. The mechanism required for the binding energy between C60 and gold has been observed to exist between C60 and many of the mirror metals (Al, Ag, Au, Cu, Ni). This binding energy is a charge transfer from the metal Fermi level into the C60 LUMO. If this bonding energy, is greater than the metals coagulation energy an Au/C60 size terminated mechanism during the formation of the gold aggregates by the adhesion of C60 to the surface is energetically favorable.

  17. Thermochemistry of Pt-Fullerene Complexes: Semiempirical Study

    Science.gov (United States)

    Voityuk, Alexander A.

    2009-07-01

    Modified Neglect of Differential Overlap (MNDO) and MNDO/d based semiempirical methods are widely employed to explore structure and thermochemistry of molecular systems. In this work, the AM1/d method has been parametrized for systems containing platinum. The proposed scheme delivers excellent performance for binding energies of Pt complexes with ethylene and large π conjugated hydrocarbons. The estimated bond energies accurately reproduce the results of MP4(SDQ) calculations and show significant improvement over DFT (B3LYP and M05) data. We apply the AM1/d scheme to explore the structure and thermochemistry of several Pt compounds with C60 and C70. The calculated binding energies of bare Pt atoms and [Pt(PH3)2] units to the fullerenes are 75 and 45 kcal/mol, respectively. We find that coordination of a single metal center to C60 activates the fullerene cage making subsequent coordination of Pt more favorable. The bond energy [C60-PtC60] is calculated to be 65 kcal/mol. The estimated reaction enthalpies are useful for exploring the stability of PtxC60 polymer systems and their interaction with phosphines. AM1/d predicts a very low barrier to rotation of the coordinated fullerenes in [Pt(C60)2]. The AM1/d scheme is computationally very efficient and can be employed to obtain fast quantitative estimates for binding energies and structural parameters of Pt complexes with large π conjugated systems like fullerenes and carbon nanotubes.

  18. Properties of casting solutions and ultrafiltration membranes based on fullerene-polyamide nanocomposites

    Directory of Open Access Journals (Sweden)

    N. N. Sudareva

    2012-03-01

    Full Text Available Poly(phenylene isophtalamide (PA was modified by fullerene C60 using solid-phase method. Novel ultrafiltration membranes based on nanocomposites containing up to 10 wt% of fullerene and carbon black were prepared. Properties of PA/C60 composites in solutions were studied by light scattering and rheological methods. The relationship between characteristics of casting solutions and properties of nanocomposite membranes was studied. Scanning electron microscopy was used for structural characterization of the membranes. It was found that increase in fullerene content in nanocomposite enhances the membrane rigidity. All nanocomposite membranes were tested in dynamic (ultrafiltration and static sorption experiments using a solution of protein mixture, with the purpose of studying protein sorption. The membranes modified by fullerene demonstrate the best values of flux reduced recovery after contact with protein solution. It was found that addition of fullerene C60 to the polymer improves technological parameters of the obtained composite membranes.

  19. Calix[4]arene-linked bisporphyrin hosts for fullerenes: binding strength, solvation effects, and porphyrin-fullerene charge transfer bands.

    Science.gov (United States)

    Hosseini, Ali; Taylor, Steven; Accorsi, Gianluca; Armaroli, Nicola; Reed, Christopher A; Boyd, Peter D W

    2006-12-13

    A calix[4]arene scaffolding has been used to construct bisporphyrin ("jaws" porphyrin) hosts for supramolecular binding of fullerene guests. Fullerene affinities were optimized by varying the nature of the covalent linkage of the porphyrins to the calixarenes. Binding constants for C60 and C70 in toluene were explored as a function of substituents at the periphery of the porphyrin, and 3,5-di-tert-butylphenyl groups gave rise to the highest fullerene affinities (26,000 M(-1) for C60). The origin of this high fullerene affinity has been traced to differential solvation effects rather than to electronic effects. Studies of binding constants as a function of solvent (toluene solubility, indicating that desolvation of the fullerene is a major factor determining the magnitude of binding constants. The energetics of fullerene binding have been determined in terms of DelatH and DeltaS and are consistent with an enthalpy-driven, solvation-dependent process. A direct relationship between supramolecular binding of a fullerene guest to a bisporphyrin host and the appearance of a broad NIR absorption band have been established. The energy of this band moves in a predictable manner as a function of the electronic structure of the porphyrin, thereby establishing its origin in porphyrin-to-fullerene charge transfer.

  20. Fullerene assemblies toward photo-energy conversions.

    Science.gov (United States)

    Shen, Yanfei; Nakanishi, Takashi

    2014-04-28

    Manipulating molecular interaction and assembly for developing various functional nanostructures with controlled dimensionality, morphology and tailored properties is currently a research focus in molecular science and materials chemistry. Particularly, the self-organization of fullerenes (i.e. C60) to form various functional assemblies has received intense interest since it can provide excellent optoelectronic properties for photo-energy conversion-induced applications such as solar cells and field effect transistors (FET). In this perspective, we describe our recent efforts toward the development in the area of fullerene molecular design and assemblies aimed at improving the photoconductivity and photo-energy (electric and thermal) conversion systems.

  1. The dramatic effect of the annealing temperature and dielectric functionalization on the electron mobility of indene-C60 bis-adduct thin films.

    Science.gov (United States)

    Orgiu, Emanuele; Squillaci, Marco A; Rekab, Wassima; Börjesson, Karl; Liscio, Fabiola; Zhang, Lei; Samorì, Paolo

    2015-03-28

    Herein we report on the charge transport properties of spin-coated thin films of an n-type fullerene derivative, i.e. the indene-C60 bis-adduct (ICBA). In particular, the effects of annealing temperature and duration as well as surface functionalization are explored. Electron mobilities approaching 0.1 cm(2) V(-1) s(-1) are reported.

  2. Co-Exposure with Fullerene May Strengthen Health Effects of Organic Industrial Chemicals

    DEFF Research Database (Denmark)

    Lehto, M.; Karilainen, T.; Rog, T.

    2014-01-01

    In vitro toxicological studies together with atomistic molecular dynamics simulations show that occupational co-exposure with C-60 fullerene may strengthen the health effects of organic industrial chemicals. The chemicals studied are acetophenone, benzaldehyde, benzyl alcohol, m-cresol, and toluene...... which can be used with fullerene as reagents or solvents in industrial processes. Potential co-exposure scenarios include a fullerene dust and organic chemical vapor, or a fullerene solution aerosolized in workplace air. Unfiltered and filtered mixtures of C-60 and organic chemicals represent different...... co-exposure scenarios in in vitro studies where acute cytotoxicity and immunotoxicity of C-60 and organic chemicals are tested together and alone by using human THP-1-derived macrophages. Statistically significant co-effects are observed for an unfiltered mixture of benzaldehyde and C-60 that is more...

  3. Dynamic solvation shell and solubility of C60 in organic solvents.

    Science.gov (United States)

    Wang, Chun I; Hua, Chi C; Chen, Show A

    2014-08-21

    The notion of (static) solvation shells has recently proved fruitful in revealing key molecular factors that dictate the solubility and aggregation properties of fullerene species in polar or ionic solvent media. Using molecular dynamics schemes with carefully evaluated force fields, we have scrutinized both the static and the dynamic features of the solvation shells of single C60 particle for three nonpolar organic solvents (i.e., chloroform, toluene, and chlorobenzene) and a range of system temperatures (i.e., T = 250-330 K). The central findings have been that, while the static structures of the solvation shell remain, in general, insensitive to the effects of changing solvent type or system temperature, the dynamic behavior of solvent molecules within the shell exhibits prominent dependence on both factors. Detailed analyses led us to propose the notion of dynamically stable solvation shell, effectiveness of which can be characterized by a new physical parameter defined as the ratio of two fundamental time constants representing, respectively, the solvent relaxation (or residence) time within the first solvation shell and the characteristic time required for the fullerene particle to diffuse a distance comparable to the shell thickness. We show that, for the five (two from the literature) different solvent media and the range of system temperatures examined herein, this parameter bears a value around unity and, in particular, correlates intimately with known trends of solubility for C60 solutions. We also provide evidence revealing that, in addition to fullerene-solvent interactions, solvent-solvent interactions play an important role, too, in shaping the dynamic solvation shell, as implied by recent experimental trends.

  4. Production of Endohedral Fullerenes by Ion Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Diener, M.D.; Alford, J. M.; Mirzadeh, S.

    2007-05-31

    derivatizing the radiofullerenes for water-solubility and a method for removing exohedral radionuclides are reported. The methods and chemistry developed during this CRADA are the crucial first steps for the development of fullerenes as a method superior to existing technologies for in vivo transport of radionuclides.

  5. Improved water solubility of neohesperidin dihydrochalcone in sweetener blends.

    Science.gov (United States)

    Benavente-García, O; Castillo, J; Del Baño, M J; Lorente, J

    2001-01-01

    Significant technological advantages in terms of sweetness synergy and hence cost-saving can be obtained if neohesperidin dihydrochalcone (NHDC) is used in sweetener blends with other intense or bulk sweeteners. The combination of NHDC with sodium saccharin or sodium cyclamate is an excellent method to improve the water solubility at room temperature of NHDC. In the case of NHDC-sodium saccharin, two different methods for blend preparation, a simple mixture and a cosolubilized mixture, can be used, with similar results obtained for solubility and solution stability properties. To improve temporally the water solubility of NHDC in combination with sodium cyclamate, it is absolutely necessary to prepare cosolubilized blends.

  6. Cobalt-catalyzed hydroalkylation of [60]fullerene with active alkyl bromides: selective synthesis of monoalkylated fullerenes.

    Science.gov (United States)

    Lu, Shirong; Jin, Tienan; Bao, Ming; Yamamoto, Yoshinori

    2011-08-17

    The Co-catalyzed hydroalkylation of C(60) with reactive alkyl bromides 1 (RBr) in the presence of Mn reductant and H(2)O at ambient temperature gave the monoalkylated C(60) (2) in good to high yields. The use of CoLn/Mn/H(2)O under Ar atmosphere is crucial for the success of the present transformation. The reaction most probably proceeds through the Co(0 or I) complex-promoted generation of a radical (R(•)) followed by addition to C(60). This hydroalkylation method was applied to the synthesis of zinc porphyrin attached C(60) (2l), dendrimer attached C(60) (2m), and fullerene dimer (2n), which were not easily available through the previously known methods.

  7. Synthesis of fullerene nanowhiskers using the liquid-liquid interfacial precipitation method and their mechanical, electrical and superconducting properties

    Science.gov (United States)

    Miyazawa, Kun'ichi

    2015-02-01

    Fullerene nanowhiskers (FNWs) are thin crystalline fibers composed of fullerene molecules, including C60, C70, endohedral, or functionalized fullerenes. FNWs display n-type semiconducting behavior and are used in a diverse range of applications, including field-effect transistors, solar cells, chemical sensors, and photocatalysts. Alkali metal-doped C60 (fullerene) nanowhiskers (C60NWs) exhibit superconducting behavior. Potassium-doped C60NWs have realized the highest superconducting volume fraction of the alkali metal-doped C60 crystals and display a high critical current density (Jc) under a high magnetic field of 50 kOe. The growth control of FNWs is important for their success in practical applications. This paper reviews recent FNWs research focusing on their mechanical, electrical and superconducting properties and growth mechanisms in the liquid-liquid interfacial precipitation method.

  8. Does the Like Dissolves Like Rule Hold for Fullerene and Ionic Liquids?

    DEFF Research Database (Denmark)

    Chaban, Vitaly V.; Maciel, C.; Fileti, E. E.

    2014-01-01

    Over 150 solvents have been probed to dissolve light fullerenes, but with a quite moderate success. We uncover unusual mutual polarizability of C-60 fullerene and selected room-temperature ionic liquids, which can be applied in numerous applications, e.g. to significantly promote solubility...

  9. Self-assembly made durable: water-repellent materials formed by cross-linking fullerene derivatives.

    Science.gov (United States)

    Wang, Jiaobing; Shen, Yanfei; Kessel, Stefanie; Fernandes, Paulo; Yoshida, Kaname; Yagai, Shiki; Kurth, Dirk G; Möhwald, Helmuth; Nakanishi, Takashi

    2009-01-01

    Fullerene flakes: A diacetylene-functionalized fullerene derivative self-organizes into flakelike microparticles (see picture). Both the diacetylene and C(60) moieties can be effectively cross-linked, which leads to supramolecular materials with remarkable resistivity to solvent, heat, and mechanical stress. Moreover, the surface of the cross-linked flakelike objects is highly durable and water-repellent.

  10. Molecular dynamics study of self-agglomeration of charged fullerenes in solvents.

    Science.gov (United States)

    Banerjee, Soumik

    2013-01-28

    The agglomeration of fullerenes in solvents is an important phenomenon that is relevant to controlled synthesis of fullerene-based nanowires as well as fullerene-based composites. The molecular aggregation in solvents depends on the atomistic interactions of fullerene with the solvent and is made complicated by the fact that fullerenes accrue negative surface charges when present in solvents such as water. In the present work, we simulated fullerenes of varying size and shape (C60, C180, C240, and C540) with and without surface charges in polar protic (water), polar aprotic (acetone), and nonpolar (toluene) solvents using molecular dynamics method. Our results demonstrate that uncharged fullerenes form agglomerates in polar solvents such as water and acetone and remain relatively dispersed in nonpolar toluene. The presence of surface charge significantly reduces agglomerate size in water and acetone. Additionally, the relative influence of surface charge on fullerene agglomeration depends on the size and geometry of the fullerene with larger fullerenes forming relatively smaller agglomerates. We evaluated the diffusion coefficients of solvent molecules within the solvation shell of fullerenes and observed that they are much lower than the bulk solvent and are strongly associated with the fullerenes as seen in the corresponding radial distribution functions. To correlate agglomerate size with the binding energy between fullerenes, we evaluated the potential of mean force between fullerenes in each solvent. Consistent with the solubility of fullerenes, binding energy between fullerenes is the greatest in water followed by acetone and toluene. The presence of charge decreases the binding energy of fullerenes in water and thus results in dispersed fullerenes.

  11. In vitro and in vivo comparative study of the phototherapy anticancer activity of hyaluronic acid-modified single-walled carbon nanotubes, graphene oxide, and fullerene

    Science.gov (United States)

    Hou, Lin; Yuan, Yujie; Ren, Junxiao; Zhang, Yinling; Wang, Yongchao; Shan, Xiaoning; Liu, Qi; Zhang, Zhenzhong

    2017-08-01

    In this work, carbon nanomaterials, single-walled carbon nanotubes (SWNT), graphene oxide (GO), and fullerene (C60) were modified by hyaluronic acid (HA) to obtain water-soluble and biocompatible nanomaterials with high tumor-targeting capacity and then the comparative study of these hyaluronic acid-modified carbon nanomaterials was made in vitro and in vivo. The conjugates of hyaluronic acid and carbon nanomaterials, namely, HA-SWNT, HA-GO, HA-C60, were confirmed by UV/Vis spectrum, Fourier transform infrared spectroscopy (FTIR), and a transmission electron microscope (TEM). After HA modification, the sizes of HA-SWNT, HA-GO, and HA-C60 were in a range of 70 to 300 nm, and all the three HA-modified materials were at negative potential, demonstrating that HA modification was in favor of extravasation of carbon materials into a tumor site due to enhanced permeability and retention effect of tumor. Photothermal conversion in vitro test demonstrated excellent photothermal sensitivity of HA-SWNT and HA-GO. But the reactive oxygen yield of HA-C60 was the highest compared with the others under visible light irradiation, which proved the good photodynamic therapy effect of HA-C60. In addition, cytotoxicity experiments exhibited that the inhibitory efficacy of HA-SWNT was the lowest, the second was HA-C60, and the highest was HA-GO, which was consistent with the uptake degree of them. While under the laser irradiation, the cell inhibition of the HA-SWNT was the highest, the second was HA-GO, and the last was HA-C60. In vivo evaluation of the three targeting carbon nanomaterials was consistent with the cytotoxicity assay results. Taken together, the results demonstrated that HA-SWNT and HA-GO were suited for photothermal therapy (PTT) agents for their good photothermal property, while HA-C60 was used as a kind of photodynamic therapy (PDT) agent for its photodynamic effect.

  12. Communication: Quantum six-dimensional calculations of the coupled translation-rotation eigenstates of H2O@C60

    Science.gov (United States)

    Felker, Peter M.; Bačić, Zlatko

    2016-05-01

    We report rigorous quantum calculations of the translation-rotation (TR) eigenstates of para- and ortho-H2O@C60. They provide a comprehensive description of the dynamical behavior of H2O inside the fullerene having icosahedral (Ih) symmetry. The TR eigenstates are assigned in terms of the irreducible representations of the proper symmetry group of H2O@C60, as well as the appropriate translational and rotational quantum numbers. The coupling between the orbital and the rotational angular momenta of the caged H2O gives rise to the total angular momentum λ, which additionally labels each TR level. The calculated TR levels allow tentative assignments of a number of transitions in the recent experimental INS spectra of H2O@C60 that have not been assigned previously.

  13. Phosphoryl choline-grafted water-soluble carbon nanotube

    Institute of Scientific and Technical Information of China (English)

    Tao Zhang; Kai Xi; Min Gu; Zheng Sheng Jiang

    2008-01-01

    Water-soluble property is the precondition of biomedical evaluation and application of carbon nanotube (CNT). Novel watersoluble CNT was synthesized in this letter by grafting phosphoryi choline (PC) onto multi-wall CNTs. Utilizing FTIR, XPS, TGAand TEM, the title CNTs were characterized and it was found that the target products could facilely dissolve in water.

  14. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    NICO

    radiation balance.4,5 Major water-soluble inorganic ions are associated with ... central area and major road systems and possible aerosol sources include biomass ..... Tanzania than at European rural sites32 and Asia.33,34. To determine the ...

  15. Water-soluble diphosphadiazacyclooctanes as ligands for aqueous organometallic catalysis

    KAUST Repository

    Boulanger, Jérôme

    2012-12-01

    Two new water-soluble diphosphacyclooctanes been synthesized and characterized by NMR and surface tension measurements. Both phosphanes proved to coordinate rhodium in a very selective way as well-defined bidentates were obtained. When used in Rh-catalyzed hydroformylation of terminal alkenes, both ligands positively impacted the reaction chemoselectivity. © 2012 Elsevier B.V.

  16. Water-soluble constituents of cumin: monoterpenoid glucosides.

    Science.gov (United States)

    Ishikawa, Toru; Takayanagi, Tomomi; Kitajima, Junichi

    2002-11-01

    From the water-soluble portion of the methanol extract of cumin (fruit of Cuminum cyminum L.), which has been used as a spice and medicine since antiquity, sixteen monoterpenoid glucosides, including twelve new compounds, were isolated. Their structures were clarified by spectral investigation.

  17. Important role of alkali atoms in A4C60

    OpenAIRE

    Gunnarsson, O.; Erwin, S. C.; Koch, E.; Martin, R. M.

    1997-01-01

    We show that hopping via the alkali atoms plays an important role for the t1u band of A4C60 (A=K, Rb), in strong contrast to A3C60. Thus the t1u band is broadened by more than 40 % by the presence of the alkali atoms. The difference between A4C60 and A3C60 is in particular due to the less symmetric location of the alkali atoms in A4C60.

  18. Formation of fullerenes in H-containing Planetary Nebulae

    CERN Document Server

    Garcia-Hernandez, D A; Garcia-Lario, P; Stanghellini, L; Villaver, E; Shaw, R A; Szczerba, R; Perea-Calderon, J V

    2010-01-01

    Hydrogen depleted environments are considered an essential requirement for the formation of fullerenes. The recent detection of C60 and C70 fullerenes in what was incorrectly interpreted as a hydrogen-poor Planetary Nebula (PN) seemed to confirm this picture. Here, we present strong evidence that challenges the current paradigm regarding fullerene formation, showing that it can take place in circumstellar environments containing hydrogen. We report the simultaneous detection of Polycyclic Aromatic Hydrocarbons (PAHs) and fullerenes towards C-rich and H-containing PNe belonging to environments with very different chemical histories such as our own Galaxy and the Small Magellanic Cloud. We suggest that PAHs and fullerenes may be formed by the photochemical processing of hydrogenated amorphous carbon. These observations have profound implications on our current understanding of the chemistry of large organic molecules as well as the chemical processing in space.

  19. Direct observation of photocarrier electron dynamics in C60 films on graphite by time-resolved two-photon photoemission

    Science.gov (United States)

    Shibuta, Masahiro; Yamamoto, Kazuo; Ohta, Tsutomu; Nakaya, Masato; Eguchi, Toyoaki; Nakajima, Atsushi

    2016-10-01

    Time-resolved two-photon photoemission (TR-2PPE) spectroscopy is employed to probe the electronic states of a C60 fullerene film formed on highly oriented pyrolytic graphite (HOPG), acting as a model two-dimensional (2D) material for multi-layered graphene. Owing to the in-plane sp2-hybridized nature of the HOPG, the TR-2PPE spectra reveal the energetics and dynamics of photocarriers in the C60 film: after hot excitons are nascently formed in C60 via intramolecular excitation by a pump photon, they dissociate into photocarriers of free electrons and the corresponding holes, and the electrons are subsequently detected by a probe photon as photoelectrons. The decay rate of photocarriers from the C60 film into the HOPG is evaluated to be 1.31 × 1012 s‑1, suggesting a weak van der Waals interaction at the interface, where the photocarriers tentatively occupy the lowest unoccupied molecular orbital (LUMO) of C60. The photocarrier electron dynamics following the hot exciton dissociation in the organic thin films has not been realized for any metallic substrates exhibiting strong interactions with the overlayer. Furthermore, the thickness dependence of the electron lifetime in the LUMO reveals that the electron hopping rate in C60 layers is 3.3 ± 1.2 × 1013 s‑1.

  20. Regulation of Glucose Oxidase Activity through Interaction with Fullerene Derivatives%Regulation of Glucose Oxidase Activity through Interaction with Fullerene Derivatives

    Institute of Scientific and Technical Information of China (English)

    Gao, Yunyan; Wang, Zhongli; Ou, Zhize; Li, Yi; Wang, Xuesong; Yang, Guoqiang

    2012-01-01

    The 2-(hydroxymethyl)pyridine modified C60 (PY-C60) and methoxydiglycol modified C60 (MDG-C60) are synthesized using Bingel-Hirsch reaction and characterized by nuclear magnetic resonance (NMR) and mass spectra. PY-C60 and MDG-C60 can bind to glucose oxidase (GOx) and quench the fluorescence of tryptophan (Trp) residue in GOx through static mechanism. The conformation of GOx is disturbed after formation of complex with these fullerene derivatives. Kinetic analysis indicates that PY-C60 and MDG-C60 may affect the catalytic activity of GOx with a partial mixed-type inhibition mechanism. In the plasma glucose concentration range (3.6--5.2 mmol·L-1), PY-C60 may significantly accelerate the catalytic velocity of GOx, however, MDG-C60 exerts almost no obvious change to the initial velocity of GOx, suggesting that elaborate design of molecular structure of fullerene derivative is very important for regulating the biological activity of fullerene-enzyme complex.

  1. Theoretical study of C60 as catalyst for dehydrogenation in LiBH4

    Science.gov (United States)

    Scheicher, Ralph H.; Li, Sa; Moyses Araujo, C.; Blomqvist, Andreas; Ahuja, Rajeev; Jena, Puru

    2011-08-01

    Complex light metal hydrides possess many properties which make them attractive as a storage medium for hydrogen, but typically catalysts are required to lower the hydrogen desorption temperature and to facilitate hydrogen uptake in the form of a reversible reaction. The overwhelming focus in the search for catalysing agents has been on compounds containing titanium, but the precise mechanism of their actions remains somewhat obscure. A recent experiment has now shown that fullerenes (C60) can also act as catalysts for both hydrogen uptake and release in lithium borohydride (LiBH4). In an effort to understand the involved mechanism, we have employed density functional theory to carry out a detailed study of the interaction between this complex metal hydride and the carbon nanomaterial. Considering a stepwise reduction of the hydrogen content in LiBH4, we find that the presence of C60 can lead to a substantial reduction of the involved H-removal energies. This effect is explained as a consequence of the interaction between the BHx - complex and the C60 entity.

  2. Synthesis and characterization of a lithium-doped fullerane (Li(x)-C60-H(y)) for reversible hydrogen storage.

    Science.gov (United States)

    Teprovich, Joseph A; Wellons, Matthew S; Lascola, Robert; Hwang, Son-Jong; Ward, Patrick A; Compton, Robert N; Zidan, Ragaiy

    2012-02-08

    Herein, we present a lithium-doped fullerane (Li(x)-C(60)-H(y)) that is capable of reversibly storing hydrogen through chemisorption at elevated temperatures and pressures. This system is unique in that hydrogen is closely associated with lithium and carbon upon rehydrogenation of the material and that the weight percent of H(2) stored in the material is intimately linked to the stoichiometric ratio of Li:C(60) in the material. Characterization of the material (IR, Raman, UV-vis, XRD, LDI-TOF-MS, and NMR) indicates that a lithium-doped fullerane is formed upon rehydrogenation in which the active hydrogen storage material is similar to a hydrogenated fullerene. Under optimized conditions, a lithium-doped fullerane with a Li:C(60) mole ratio of 6:1 can reversibly desorb up to 5 wt % H(2) with an onset temperature of ~270 °C, which is significantly less than the desorption temperature of hydrogenated fullerenes (C(60)H(x)) and pure lithium hydride (decomposition temperature 500-600 and 670 °C respectively). However, our Li(x)-C(60)-H(y) system does not suffer from the same drawbacks as typical hydrogenated fullerenes (high desorption T and release of hydrocarbons) because the fullerene cage remains mostly intact and is only slightly modified during multiple hydrogen desorption/absorption cycles. We also observed a reversible phase transition of C(60) in the material from face-centered cubic to body-centered cubic at high levels of hydrogenation.

  3. Fullerene C-60 with cytoprotective and cytotoxic potential : Prospects as a novel treatment agent in Dermatology?

    NARCIS (Netherlands)

    Rondags, Angelica; Yuen, Wing Yan; Jonkman, Marcel F.; Horvath, Barbara

    2017-01-01

    It is known that an excess amount of (oxygen) radicals in the skin can lead to (local cellular) oxidative stress. From one side, oxidative stress can contribute to the existence of various (inflammatory) skin diseases such as acne vulgaris and alopecia, as well as to accelerated photo-ageing of the

  4. Co-exposure with fullerene may strengthen health effects of organic industrial chemicals.

    Directory of Open Access Journals (Sweden)

    Maili Lehto

    Full Text Available In vitro toxicological studies together with atomistic molecular dynamics simulations show that occupational co-exposure with C60 fullerene may strengthen the health effects of organic industrial chemicals. The chemicals studied are acetophenone, benzaldehyde, benzyl alcohol, m-cresol, and toluene which can be used with fullerene as reagents or solvents in industrial processes. Potential co-exposure scenarios include a fullerene dust and organic chemical vapor, or a fullerene solution aerosolized in workplace air. Unfiltered and filtered mixtures of C60 and organic chemicals represent different co-exposure scenarios in in vitro studies where acute cytotoxicity and immunotoxicity of C60 and organic chemicals are tested together and alone by using human THP-1-derived macrophages. Statistically significant co-effects are observed for an unfiltered mixture of benzaldehyde and C60 that is more cytotoxic than benzaldehyde alone, and for a filtered mixture of m-cresol and C60 that is slightly less cytotoxic than m-cresol. Hydrophobicity of chemicals correlates with co-effects when secretion of pro-inflammatory cytokines IL-1β and TNF-α is considered. Complementary atomistic molecular dynamics simulations reveal that C60 co-aggregates with all chemicals in aqueous environment. Stable aggregates have a fullerene-rich core and a chemical-rich surface layer, and while essentially all C60 molecules aggregate together, a portion of organic molecules remains in water.

  5. Investigation of tribological properties of composite C60-LB films

    Institute of Scientific and Technical Information of China (English)

    YANG Guanghong; ZHANG Xingtang; XUN Jun; JIANG Xiaohong; ZHANG Pingyu; DU Zuliang

    2006-01-01

    Composite C60-LB films were fabricated by the Langmuir-Blodgett (LB) technique, their micro- structures, micro- and macro-tribological properties were investigated using atomic force microscope/ friction force microscope (AFM/FFM). The results showed that in the confined C60-LB films there were two kinds of structures for the special C60 assembly: grain diameters of one kind were in the range of 150-230 nm; the other was smaller than 20 nm. Mi-cro-tribological studies showed that topographical images of tiny C60 aggregates (<20 nm) were con-sistent with their frictional ones very well, namely, low friction occurred on tiny C60 aggregates compared with fatty chains LB monolayer, and 'Micro-rolling effect' was apparent; but for big large ones frictional forces were relatively high and 'ratchet mechanism' was seen apparently. Macro-tribological data proved large C60 aggregates had wear resistance and load-carrying capacities and anti-wear lives for com- posite C60-LB films were prolonged greatly with dis-persibility of C60 improved and its grain diameter re-duced. Tiny C60 aggregates were mainly the lubricating agents. Friction coefficients of composite C60-LB films gradually reduced with loads increasing having the same friction coefficient-load relations with boundary lubrication films.

  6. Tuning the molecular order of C60-based self-assembled monolayers in field-effect transistors.

    Science.gov (United States)

    Schmaltz, Thomas; Khassanov, Artoem; Steinrück, Hans-Georg; Magerl, Andreas; Hirsch, Andreas; Halik, Marcus

    2014-11-07

    The control of order in organic semiconductor systems is crucial to achieve desired properties in electronic devices. We have studied the order in fullerene functionalized self-assembled monolayers by mixing the active molecules with supporting alkyl phosphonic acids of different chain length. By adjusting the length of the molecules, structural modifications of the alignment of the C60 head groups within the SAM can be tuned in a controlled way. These changes on the sub-nanometre scale were analysed by grazing incidence X-ray diffraction and X-ray reflectivity. To study the electron transport properties across these layers, self-assembled monolayer field-effect transistors (SAMFETs) were fabricated containing only the single fullerene monolayer as semiconductor. Electrical measurements revealed that a high 2D crystalline order is not the only important aspect. If the fullerene head groups are too confined by the supporting alkyl phosphonic acid molecules, defects in the crystalline C60 film, such as grain boundaries, start to strongly limit the charge transport properties. By close interpretation of the results of structural investigations and correlating them to the results of electrical characterization, an optimum chain length of the supporting alkyl phosphonic acids in the range of C10 was determined. With this study we show that minor changes in the order on the sub-nanometre scale, can strongly influence electronic properties of functional self-assembled monolayers.

  7. Synthesis of fullerene-acene dyads

    Science.gov (United States)

    Cho, Claire Eunhye

    Organic photovoltaic (OPV) cells present potential for industrial use because of their possible low cost production. However, their relatively low efficiencies render them impractical for implementation. A comprehensive understanding of the photophysical process is necessary for eventual development of high efficiency OPV cells. Studying photophysical processes of well-defined structures such as dyad or triad molecules may give insight into their photophysical processes. In this study, we selected pentacene derivatives as electron donors and fullerenes as electron acceptors for dyad and triad molecules with well-defined structures. Several new types of organothiosubstituted 6,13-dihydropentacenes with terminal functionality including carboxylic acid, alcohol and amine groups were synthesized. A sterically hindered pentacene derivative was also prepared in order to prevent cycloaddition between C60 and pentacene. Functionalized fullerenes were synthesized for use as electron acceptors. Numerous reaction methods were attempted toward the synthesis of a donor/acceptor dyad with pentacene and fullerene derivatives. However, hydroamination of pristine C 60 using a diamino dihydropentacene derivative was the only successful method demonstrated to link C60 and dihydropentacene derivatives.

  8. Growth of centimeter-sized C60 single crystals

    Institute of Scientific and Technical Information of China (English)

    李宏年; 徐亚伯; 张建华; 何丕模; 李海洋; 吴太权; 鲍世宁

    2001-01-01

    C60 single crystals larger than one centimeter in size are grown with vapor method by nucleation control and by a proper time-dependent temperature process which allows only one nucleus growing larger and larger. X-ray diffraction patterns exhibit the high quality of the sample. As an example of the applications of large single C60 crystals,svnchrotron radiation photoemission spectra are measured to investigate the fine structure of valence bands of C60 crystals.

  9. Mechanisms for oral absorption of poorly water-soluble compounds

    DEFF Research Database (Denmark)

    Lind, Marianne Ladegaard

    in the development of lipid-based formulations. However, in order for optimum formulations to be developed, knowledge of the mechanisms of absorption of poorly water-soluble drug substances is desired. Accordingly, the purpose of this PhD study was to study the effects of endogenous surfactants (bile salts...... the intake of a lipid-rich meal can increase the bioavailability due to slower gastric emptying, increased solubilization of the drug substance in the intestinal fluids by endogenous and exogenous components, inhibition of efflux carriers and induction of intestinal lymphatic transport. Some...... of these processes can also be obtained by formulating the poorly water-soluble drug substances in lipid-based formulations. Then the drug substance is in solution when administered. Consequently, an enhanced and less variable bioavailability can be obtained, and this has led to an increasing interest...

  10. Diamond nucleation on surface of C60 thin layers

    Institute of Scientific and Technical Information of China (English)

    杨国伟; 袁放成; 刘大军; 何金田; 张兵临

    1997-01-01

    Diamond nucleation on the surface of C60 thin layers and intermediate layer of Si substrates are studied by scanning electron microscopy (SEM). The cross-section SEM images of diamond films show that diamond grains really nucleate on the surface of C60 thin layers. The SEM images of diamond nucleating sites show the nucleating aggregation of diamond on C60 surfaces. The preferential oriented diamond films are observed. The plasma pre-treatment of C60 sublimating layers is a key factor for diamond nucleation.

  11. Cooperative Assembly of Magic Number C60-Au Complexes

    Science.gov (United States)

    Xie, Yang-Chun; Tang, Lin; Guo, Quanmin

    2013-11-01

    We report the assembly of magic number (C60)m-(Au)n complexes on the Au(111) surface. These complexes have a unique structure consisting of a single atomic layer Au island wrapped by a self-selected number (seven, ten, or twelve) of C60 molecules. The smallest structure consisting of 7 C60 molecules and 19 Au atoms, stable up to 400 K, has a preferred orientation on the surface. We propose a globalized metal-organic coordination mechanism for the stability of the (C60)m-(Au)n complexes.

  12. New water-soluble carbamate ester derivatives of resveratrol

    OpenAIRE

    Andrea Mattarei; Massimo Carraro; Michele Azzolini; Cristina Paradisi; Mario Zoratti; Lucia Biasutto

    2014-01-01

    Low bioavailability severely hinders exploitation of the biomedical potential of resveratrol. Extensive phase-II metabolism and poor water solubility contribute to lowering the concentrations of resveratrol in the bloodstream after oral administration. Prodrugs may provide a solution—protection of the phenolic functions hinders conjugative metabolism and can be exploited to modulate the physicochemical properties of the compound. We report here the synthesis and characterization of carb...

  13. Water Soluble Iron aminoclay for Catalytic Reduction of Nitrophenol

    Directory of Open Access Journals (Sweden)

    S. ANBU ANJUGAM VANDARKUZHALI

    2013-06-01

    Full Text Available Water soluble iron decorated phyllosilicate is synthesized through one pot sol-gel synthesis by a wet chemical method using NaBH4 as reducing agent. The as-synthesized nanocomposite is characterized by powder-XRD and TGA techniques. The morphology of the composite is obtained using HRSEM and HRTEM. The prepared nanocomposite is an efficient catalyst for the reduction of nitrophenol.

  14. Photodynamics of a constrained parachute-shaped fullerene-porphyrin dyad

    NARCIS (Netherlands)

    D.I. Schuster; P. Cheng; S.R. Wilson; V. Prokhorenko; M. Katterle; A.R. Holzwarth; S.E. Braslavsky; G. Klihm; R.M. Williams

    1999-01-01

    The pronounced ability of fullerene C60 to act as an electron and energy acceptor has led to the synthesis of a large number of compounds in which C60 is covalently linked to photoactivatable groups which can serve as potential donors. Such compounds are of interest as model systems for photosynthet

  15. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    Energy Technology Data Exchange (ETDEWEB)

    Anandhakumar, S.; Debapriya, M. [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India); Nagaraja, V. [Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012 (India); Raichur, Ashok M., E-mail: amr@materials.iisc.ernet.in [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India)

    2011-03-12

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO{sub 3} particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  16. Hybrid solar cells from water-soluble polymers

    Directory of Open Access Journals (Sweden)

    James T. McLeskey

    2006-01-01

    Full Text Available We report on the use of a water-soluble, light-absorbing polythiophene polymer to fabricate novel photovoltaic devices. The polymer is a water-soluble thiophene known as sodium poly[2-(3-thienyl-ethoxy-4-butylsulfonate] or PTEBS. The intention is to take advantage of the properties of conjugated polymers (flexible, tunable, and easy to process and incorporate the additional benefits of water solubility (easily controlled evaporation rates and environmentally friendly. The PTEBS polythiophene has shown significant photovoltaic response and has been found to be effective for making solar cells. To date, solar cells in three different configurations have been produced: titanium dioxide (TiO2 bilayer cells, TiO2 bulk heterojunction solar cells, and carbon nanotubes (CNTs in bulk heterojunctions. The best performance thus far has been achieved with TiO2 bilayer devices. These devices have an open circuit voltage (Voc of 0.84V, a short circuit current (Jsc of 0.15 mA/cm2, a fill factor (ff of 0.91, and an efficiency (η of 0.15 %.

  17. C60 superstructure and carbide formation on the Al-terminated Al9Co2(001 ) surface

    Science.gov (United States)

    Ledieu, J.; Gaudry, É.; de Weerd, M.-C.; Gille, P.; Diehl, R. D.; Fournée, V.

    2015-04-01

    We report the formation of an ordered C60 monolayer on the Al9Co2 (001) surface using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), x-ray and ultraviolet photoelectron spectroscopy (XPS/UPS), and ab initio calculations. Dosing fullerenes at 300 K results in a disordered overlayer. However, the adsorption of C60 with the sample held between 573-673 K leads to a [4, -2 ∣1 ,3 ] phase. The growth of C60 proceeds with the formation of two domains which are mirror symmetric with respect to the [100] direction. Within each domain, the superstructure unit cell contains six molecules and this implies an area per fullerene equal to 91 Å2. The molecules exhibit two types of contrast (bright and dim) which are bias dependent. The adsorption energies and preferred molecular configuration at several possible adsorption sites have been determined theoretically. These calculations lead to a possible scheme describing the configuration of each C60 in the observed superstructure. Several defects (vacancies, protrusions,…) and domain boundaries observed in the film are also discussed. If the sample temperature is higher than 693 K when dosing, impinging C60 molecules dissociate at the surface, hence leading to the formation of a carbide film as observed by STM and LEED measurements. The formation of Al4C3 domains and the molecular dissociation are confirmed by XPS/UPS measurements acquired at different stages of the experiment. The cluster substructure present at the Al9Co2 (001) surface dictates the carbide domain orientations.

  18. Gas Phase Absorption Spectroscopy of C+60 and C+70 in a Cryogenic Ion Trap: Comparison with Astronomical Measurements

    Science.gov (United States)

    Campbell, E. K.; Holz, M.; Maier, J. P.; Gerlich, D.; Walker, G. A. H.; Bohlender, D.

    2016-05-01

    Recent low-temperature laboratory measurements and astronomical observations have proved that the fullerene cation {{{C}}}60+ is responsible for four diffuse interstellar bands (DIBs). These absorptions correspond to the strongest bands of the lowest electronic transition. The gas phase spectrum below 10 {{K}} is reported here for the full wavelength range encompassed by the electronic transition. The absorption spectrum of {{{C}}}70+, with its origin band at 7959.2 {{\\mathringA }}, has been obtained under similar laboratory conditions. Observations made toward the reddened star {HD} 183143 were used in a specific search for the absorption of these fullerene cations in diffuse clouds. In the case of {{{C}}}60+, one further band in the astronomical spectrum at 9348.5 \\mathringA is identified, increasing the total number of assigned DIBs to five. Numerous other {{{C}}}60+ absorptions in the laboratory spectrum are found to lie below the astronomical detection limit. Special emphasis is placed on the laboratory determination of absolute absorption cross-sections. For {{{C}}}60+ this directly yields a column density, N({{{C}}}60+), of 2× {10}13 {{{cm}}}-2 in diffuse clouds, without the need to rely on theoretical oscillator strengths. The intensity of the {{{C}}}70+ electronic transition in the range 7000-8000 Å is spread over many features of similar strength. Absorption cross-section measurements indicate that even for a similar column density, the individual absorption bands of {{{C}}}70+ will be too weak to be detected in the astronomical spectra, which is confirmed giving an upper limit of 2 {{m\\mathringA }} to the equivalent width. Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council of Canada, the Institut National des Sciences de l’Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

  19. Algebraic theory of endohedrally confined diatomic molecules: application to H$_2$@C$_{60}$

    CERN Document Server

    Fortunato, Lorenzo

    2016-01-01

    A simple and yet powerful approach for modeling the structure of endohedrally confined diatomic molecules is introduced. The theory, based on a $u(4)\\oplus u(3)$ dynamical algebra, combines the vibron model with an isotropic three dimensional oscillator. The first describes the internal roto-vibrations degrees of freedom of the molecule, while the second takes into account the confined molecule center-of-mass degrees of freedom. A resulting subalgebra chain is connected to the underlying physics and the model is applied to the prototypical case of H$_2$ caged in a fullerene molecule. The spectrum of the supramolecular complex H$_2$@C$_{60}$ is described with a few parameters and predictions for not yet detected levels are made. Our fits suggest that the quantum numbers of a few lines should be reassigned to obtain better agreement with data.

  20. C60 as an Efficient n-Type Compact Layer in Perovskite Solar Cells.

    Science.gov (United States)

    Wojciechowski, Konrad; Leijtens, Tomas; Siprova, Svetlana; Schlueter, Christoph; Hörantner, Maximilian T; Wang, Jacob Tse-Wei; Li, Chang-Zhi; Jen, Alex K-Y; Lee, Tien-Lin; Snaith, Henry J

    2015-06-18

    Organic-inorganic halide perovskite solar cells have rapidly evolved over the last 3 years. There are still a number of issues and open questions related to the perovskite material, such as the phenomenon of anomalous hysteresis in current-voltage characteristics and long-term stability of the devices. In this work, we focus on the electron selective contact in the perovskite solar cells and physical processes occurring at that heterojunction. We developed efficient devices by replacing the commonly employed TiO2 compact layer with fullerene C60 in a regular n-i-p architecture. Detailed spectroscopic characterization allows us to present further insight into the nature of photocurrent hysteresis and charge extraction limitations arising at the n-type contact in a standard device. Furthermore, we show preliminary stability data of perovskite solar cells under working conditions, suggesting that an n-type organic charge collection layer can increase the long-term performance.

  1. Coupling of Surface and Volume Dipole Oscillations in C-60 Molecules

    CERN Document Server

    Brack, M; Murthy, M V N

    2007-01-01

    We first give a short review of the ``local-current approximation'' (LCA), derived from a general variation principle, which serves as a semiclassical description of strongly collective excitations in finite fermion systems starting from their quantum-mechanical mean-field ground state. We illustrate it for the example of coupled translational and compressional dipole excitations in metal clusters. We then discuss collective electronic dipole excitations in C$_{60}$ molecules (Buckminster fullerenes). We show that the coupling of the pure translational mode (``surface plasmon'') with compressional volume modes in the semiclasscial LCA yields semi-quantitative agreement with microscopic time-dependent density functional (TDLDA) calculations, while both theories yield qualitative agreement with the recent experimental observation of a ``volume plasmon''.

  2. Effect of the C/O ratio on the C 60 and C 70 formation rates in soot synthesised by laser pyrolysis of benzene-based mixtures

    Science.gov (United States)

    Ténégal, F.; Petcu, S.; Herlin-Boime, N.; Armand, X.; Mayne, M.; Reynaud, C.

    2001-02-01

    The effect of varying the C to O atomic ratio on the formation of fullerenes in sooting flames produced by the laser pyrolysis of benzene-based mixtures was investigated. Infrared spectra were recorded on soot toluene extracts and quantification of C 60 and C 70 was performed by High Performance Liquid Chromatography. A strong increase of the fullerenes yield (C 60+C 70) was observed with decreasing C/O ratio (2.2-1.2). The lowering of the C/O ratio was also found to influence dramatically the ratio of C 60 to C 70 through an increase of the C 60 yield faster than the C 70 one. These two effects can be fully interpreted by a kinetically based argument. A strong increase of the fullerenes content was also observed with decreasing residence time in the reaction flame, and a maximum total yield of 0.23% was reached with high conversion rates (from benzene to soot). Ponderable amounts of C 84 were also quantified.

  3. Electron elastic scattering and low-frequency bremsstrahlung on A@$C_{60}$: A model static approximation

    CERN Document Server

    Dolmatov, V K; Cooper, M B; Hunter, M E

    2015-01-01

    Electron elastic-scattering phase shifts and cross sections along with the differential and total cross sections and polarization of low-frequency bremsstrahlung upon low-energy electron collision with endohedral fullerenes $A$@C$_{60}$ are theoretically scrutinized versus the nature, size and spin of the encapsulated atom $A$. The case-study-atoms $A$ are N, Ar, Cr, Mn, Mo, Tc, Xe, Ba, and Eu. They are thoughtfully picked out of different rows of the periodic table. The study is performed in the framework of a model static approximation. There, both the encapsulated atom $A$ and C$_{60}$ cage are regarded as non-polarizable targets. The C$_{60}$ cage is modeled by an attractive spherical annular potential well. The study provides the most complete initial understanding of how the processes of interest might evolve upon electron collision with various $A$@C$_{60}$. Calculated results identify the most interesting and/or useful future measurements or more rigorous calculations of an electron+$A$@C$_{60}$ colli...

  4. Fullerenes as potential collectors of noble metals in carbon-bearing geological formations

    Directory of Open Access Journals (Sweden)

    Voytekhovsky Yu.L.

    2015-06-01

    Full Text Available The results of computer modelling of fullerenes in the Bartell's restrictions have been suggested in the paper. The inner volumes of all the possible C60 to C100 fullerenes have been calculated. The numbers of dopping Au, Ag, Pt, and Pd atoms have been found for the most stable (symmetrical with no adjacent pentagons structures. The inner volume has been stated to be mostly dependent from the number of fullerene-forming atoms than from the symmetry point group. The elongated but not spherical fullerenes possess the biggest inner volumes for the given number of carbon atoms

  5. Synthesis of Fullerene by Pyrolysis of Acetylene in Thermal HF-Plasma

    Institute of Scientific and Technical Information of China (English)

    ZHU Yanjuan; ZHANG Guofu; ZHANG Wei; LIN Tianjin; XIE Hongbo; LIU Qiuxiang; ZHANG Haiyan

    2007-01-01

    Carbon soot containing fullerene was continuously produced in volume by pyrolyzing acetylene in thermal HF-Plasma. The characteristics of the carbon soot and C60 were analyzed by thtransmission electron microscopy, UV/visible, IR and Raman spectroscopy. The results show that the main ingredients of the carbon soot with size of about 25 nm are amorphous carbon, graphite and fullerene. The fullerene yield in carbon soot is about 2.5 g·h-1. Compared with the graphite arc discharge method, the acetylene thermal plasma method is a preferential one for synthesis of fullerene.

  6. Molecular-dynamics simulations of energetic C60 impacts on (2×1)-(100) silicon

    Science.gov (United States)

    Hu, Xiaoyuan; Albe, Karsten; Averback, Robert S.

    2000-07-01

    Single impacts of energetic C60 clusters on (2×1)-(100) silicon substrates are studied by molecular-dynamics simulations. The role of impact energies and internal cluster energy are investigated in detail. Six different energy regimes can be identified at the end of the ballistic phase: At thermal energies below 20 eV the fullerene cages undergo elastic deformation, while impinging on the surface, and are mostly chemisorpted on top of the (2×1)-dimer rows. Between 20 and 100 eV the cage structure is preserved after the collision, but the cluster comes to rest within a few monolayers of the silicon surface. At energies of 100-500 eV the cluster partially decomposes and small coherent carbon caps are embedded in the surface. At higher energies up to 1.5 keV complete decomposition of the fullerene cluster occurs and an amorphous zone is formed in the subsurface area. At energies greater than approximately 1.5 keV craters form and above 6 keV sputtering becomes significant. In all cases the substrate temperature is of minor influence on the final result, but the projectile temperature is important for impacts at lower energies (interesting possibility for controlled implantation of C in Si at high local concentrations, which might allow the formation of silicon carbide.

  7. The detection of C60 in the well-characterized planetary nebula M1-11

    CERN Document Server

    Otsuka, Masaaki; Hyung, S; Sargent, B A; Meixner, M; Tajitsu, A; Yanagisawa, K

    2013-01-01

    We performed multiwavelength observations of the young planetary nebula (PN) M1-11 and obtained its elemental abundances, dust mass, and the evolutionary status of the central star. The AKARI/IRC, VLT/VISIR, and Spitzer/IRS spectra show features due to carbon-rich dust, such as the 3.3, 8.6, and 11.3 um features due to polycyclic aromatic hydrocarbons (PAHs), a smooth continuum attributable to amorphous carbon, and the broad 11.5 and 30 um features often ascribed to SiC and MgS, respectively. We also report the presence of an unidentified broad feature at 16-22 um, similar to the feature found in Magellanic Cloud PNe with either C-rich or O-rich gas-phase compositions. We identify for the first time in M1-11 spectral lines at 8.5 (blended with PAH), 17.3, and 18.9 um that we attribute to the C60 fullerene. This identification is strengthened by the fact that other Galactic PNe in which fullerenes are detected, have similar central stars, similar gas-phase abundances, and a similar dust composition to M1-11. T...

  8. Inverse photoemission studies of C-60 on Au(110)

    NARCIS (Netherlands)

    Pedio, M.; Grilli, M.L.; Ottaviani, C.; Capozi, M.; Quaresima, C.; Perfetti, P.; Thiry, P.A.; Caudano, R.; Rudolf, P.

    1995-01-01

    The unoccupied states of C60 have been studied for single monolayer and multilayer coverages on Au(110) with Inverse Photoemission Spectroscopy (IPES). In agreement with previous results on C60 on gold, we find that only the first monolayer, which is chemisorbed, shows a different spectrum compared

  9. Degradability of aged aquatic suspensions of C60 nanoparticles

    DEFF Research Database (Denmark)

    Hartmann, B.; Buendia, Inmaculada M.; Baun, Anders

    2011-01-01

    for ready biodegradability. Two suspensions of nC60 were prepared by stirring and aged under indirect exposure to sunlight for 36 months, which resulted in relatively stable suspensions with a dark-brown colour. The suspended nC60 could not be extracted into toluene and indicating that the particles were...

  10. Synthesis and Photophysical Properties of C60-carbazole Adducts

    Institute of Scientific and Technical Information of China (English)

    YIN ,Gui(尹桂); YIN,Gui; MAO,Xin-Ping(毛新平); MAO,Xin-Ping; SUO,Zhi-Yong(锁志勇); SUO,Zhi-Yong; XU,Zheng(徐正); XU,Zheng

    2001-01-01

    Three C60-cartazole adducts have been synthesized by 1,3-dipolar cycloaddition reaction.Intramolecular energy/electron transfer from carbazole to C60 was observed by steady-state absorption and fluorescence spectra.The fluorescence spectra of these adducts were similau to each other and dependent on the excitation wavelength and solvent.

  11. Synthesis of novel organo-phosphorus C60 dimers

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Carbon bridged organophosphorus C60 dimers were obtained by the reaction of aminome- thylenebisphosphonate anion with C60 and fully characterized by 1HNMR, 31PNMR, 13CNMR, FT- MALDI-MS, FT-IR, UV-Vis, DEPT and HMBC, and the dimeric compounds undergo hydrolysis by using TMSI.

  12. Adsorption of sodium and cesium on aggregates of C60

    Science.gov (United States)

    Harnisch, Martina; Daxner, Matthias; Scheier, Paul; Echt, Olof

    2016-09-01

    We explore the formation of C60 sodium and C60 cesium complexes in superfluid helium nanodroplets. Anomalies in mass spectra of these doped droplets reveal anomalies in the stability of ions. (C60) m Cs+ n ions ( m ≤ 6) are particularly abundant if they contain n = 6 m + 1 cesium atoms; (C60) m Cs2+ n dications ( m ≤ 3 or 5) are abundant if n = 6 m + 2. These findings are consistent with the notion that alkali metal atoms (A) transfer their valence electrons into the three-fold degenerate lowest unoccupied orbital of C60, resulting in particularly stable C60A6 building blocks. However, (C60) 4CsCs2+ n dications display an entirely different pattern; instead of an expected anomaly at n = 6 × 4 + 2 = 26 we observe a strong odd-even alternation starting at n = 6. Also surprising is the effect of adding one H2O or CO2 molecule to (C60) m Cs n mono- or dications; anomalies shift by two units as if the impurity were acting as an acceptor for two valence electrons from the alkali metal atoms.

  13. Charge separation and (triplet) recombination in diketopyrrolopyrrole-fullerene triads

    NARCIS (Netherlands)

    Karsten, Bram P.; Bouwer, Ricardo K. M.; Hummelen, Jan C.; Williams, Rene M.; Janssen, Rene A. J.

    2010-01-01

    Synthesis and photophysics of two diketopyrrolopyrrole-based small band gap oligomers, end-capped at both ends with C(60) are presented. Upon photoexcitation of the oligomer, ultrafast energy transfer to the fullerene occurs (similar to 0.5 ps), followed by an electron transfer reaction. Femtosecond

  14. A novel route towards high quality fullerene-pillared graphene

    NARCIS (Netherlands)

    Spyrou, Konstantinos; Kang, Longtian; Diamanti, Eumorfia K.; Gengler, Regis Y.; Gournis, Dimitrios; Prato, Maurizio; Rudolf, Petra

    A new approach for the synthesis of graphite intercalation compounds (GICs), by the help of co-intercalant molecules, has been observed. In the present work, we demonstrate the successful incorporation of fullerene (C-60) molecules between the graphene sheets aided by the preceding intercalation of

  15. A novel route towards high quality fullerene-pillared graphene

    NARCIS (Netherlands)

    Spyrou, Konstantinos; Kang, Longtian; Diamanti, Eumorfia K.; Gengler, Regis Y.; Gournis, Dimitrios; Prato, Maurizio; Rudolf, Petra

    2013-01-01

    A new approach for the synthesis of graphite intercalation compounds (GICs), by the help of co-intercalant molecules, has been observed. In the present work, we demonstrate the successful incorporation of fullerene (C-60) molecules between the graphene sheets aided by the preceding intercalation of

  16. Synthetic Strategies towards Fullerene-Rich Dendrimer Assemblies

    Directory of Open Access Journals (Sweden)

    Jean-François Nierengarten

    2012-02-01

    Full Text Available The sphere-shaped fullerene has attracted considerable interest not least due to the peculiar electronic properties of this carbon allotrope and the fascinating materials emanating from fullerene-derived structures. The rapid development and tremendous advances in organic chemistry allow nowadays the modification of C60 to a great extent by pure chemical means. It is therefore not surprising that the fullerene moiety has also been part of dendrimers. At the initial stage, fullerenes have been examined at the center of the dendritic structure mainly aimed at possible shielding effects as exerted by the dendritic environment and light-harvesting effects due to multiple chromophores located at the periphery of the dendrimer. In recent years, also many research efforts have been devoted towards fullerene-rich nanohybrids containing multiple C60 units in the branches and/or as surface functional groups. In this review, synthetic efforts towards the construction of dendritic fullerene-rich nanostructures have been compiled and will be summarized herein.

  17. Hierarchically organized soft-materials based on fullerenes

    Science.gov (United States)

    Nakanishi, Takashi

    2009-04-01

    Simple chemical modifications of fullerene (C60) with long aliphatic chains provide novel type amphiphilic molecules playing in organic solvents due to the two different intermolecular interactions, namely π-π on C60 and van der Waals interactions on aliphatic chain moieties, respectively, and open a door developing supramolecular soft-materials having hierarchically organized architectures, various morphologies and functions based on fullerenes. By tuning the length and number of aliphatic chains on the derivatives as well as experimental conditions such as solvents, temperature, substrates for preparation of the assemblies, the assembled fullerenes showed various faces such as creating of many unique-shaped objects with controlled their dimensionality. For instance, nanowires and thin disks with single bilayer thickness in nanometer size, globular, fibrous, conical objects in mesoscopic (sub-micrometer) scale and flower-shaped and direction-controlled spiral objects in micrometer scale are obtained. As bulk states, thermotropic liquid crystals and room temperature (isotropic) liquid fullerenes are interestingly prepared from this molecular designs and showed not only their fluid natures and comparably high carrier mobility as fullerene-based organic-semiconductor phenomena. In addition, nano-carbon superhydrophobic surface with fractal morphology of the two-tier roughness on a nano- and microscopic scale was created from one of the supramolecular objects. The all of hierarchical supramolecular assemblies describing in this review is derived from fine-tuning intermolecular interactions of fullerene derivatives bearing long aliphatic chains.

  18. Binding of fullerenes to amyloid beta fibrils: size matters.

    Science.gov (United States)

    Huy, Pham Dinh Quoc; Li, Mai Suan

    2014-10-01

    Binding affinity of fullerenes C20, C36, C60, C70 and C84 for amyloid beta fibrils is studied by docking and all-atom molecular dynamics simulations with the Amber force field and water model TIP3P. Using the molecular mechanic-Poisson Boltzmann surface area method one can demonstrate that the binding free energy linearly decreases with the number of carbon atoms of fullerene, i.e. the larger is the fullerene size, the higher is the binding affinity. Overall, fullerenes bind to Aβ9-40 fibrils stronger than to Aβ17-42. The number of water molecules trapped in the interior of 12Aβ9-40 fibrils was found to be lower than inside pentamer 5Aβ17-42. C60 destroys Aβ17-42 fibril structure to a greater extent compared to other fullerenes. Our study revealed that the van der Waals interaction dominates over the electrostatic interaction and non-polar residues of amyloid beta peptides play the significant role in interaction with fullerenes providing novel insight into the development of drug candidates against Alzheimer's disease.

  19. Energy loss spectroscopy of Buckminster C60 with twisted electrons: Influence of orbital angular momentum transfer on plasmon generation

    CERN Document Server

    Schüler, M

    2016-01-01

    Recent experimental progress in creating and controlling singular electron beams that carry orbital angular momentum allows for new types of local spectroscopies. We theoretically investigate the twisted-electron energy loss spectroscopy (EELS) from the C60 fullerene. Of particular interest are the strong multipolar collective excitations and their selective response to the orbital angular momentum of the impinging electron beam. Based on ab-initio calculations for the collective response we compute EELS signals with twisted electron beams and uncover the interplay between the plasmon polarity and the amount of angular momentum transfer.

  20. Probing confinement resonances by photoionizing Xe inside a C60+ molecular cage

    Science.gov (United States)

    Phaneuf, R. A.; Kilcoyne, A. L. D.; Aryal, N. B.; Baral, K. K.; Thomas, C. M.; Esteves-Macaluso, D. A.; Lomsadze, R.; Gorczyca, T. W.; Ballance, C. P.; Manson, S. T.; Hasoglu, M. F.; Hellhund, J.; Schippers, S.; Müller, A.

    2014-05-01

    Double photoionization accompanied by loss of n C atoms (n = 0 , 2 , 4 , 6) was investigated by merging beams of Xe@C60+ ions and synchrotron radiation and measuring the yields of product ions. The giant 4 d dipole resonance of the caged Xe atom has a prominent signature in the cross section for these product channels, which together account for 6 . 2 +/- 1 . 4 of the total Xe 4 d oscillator strength of 10. Compared to that for a free Xe atom, the oscillator strength is redistributed in photon energy due to multipath interference of outgoing Xe 4 d photoelectron waves that may be transmitted or reflected by the spherical C60+ molecular cage, yielding so-called confinement resonances. The data are compared with an earlier measurement and with theoretical predictions for this single-molecule photoelectron interferometer system. Relativistic R-matrix calculations for the Xe atom in a spherical potential shell representing the fullerene cage show the sensitivity of the interference pattern to the molecular geometry.

  1. Effects of sulfite ions on water-soluble chlorophyll proteins

    Energy Technology Data Exchange (ETDEWEB)

    Sugahara, K.; Uchida, S.; Takimoto, M.

    1980-01-01

    To clarify the mechanisms and processes of chlorophyll destruction and the relation to the appearance of visible symptoms in SO/sub 2/-injured plants, model experiments were carried out by utilizing the peculiar properties of a water-soluble chlorophyll protein from Chenopodium album. The acceleration of chlorophyll destruction by sulfite ions under aerobic and illuminated conditions, reported previously in organic solvent, was not observed for the water-soluble pigment-protein complex, even in 4 x 10/sup -2/ M sulfite. This indicates that pigments are stabilized by combining with protein molecules. On comparison of pigment destruction between the reconstituted chlorophyll a- and chlorophyllide a-proteins in the presence of sulfite ions, the former was slightly sensitive to sulfite ions. On the other hand, it was demonstrated that photoconversion of water-soluble chlorophyll protein was inhibited by denaturation of the protein moiety caused by sulfite ions in the presence of light. In addition it was shown that it was necessary for the pigment absorbing the light energy to be structurally related to the protein moiety for inhibition of photoconversion. From these results, the inhibition processes of photoconversion are inferred as follows: conformational changes of apoprotein molecules were induced by light energy absorbed by the pigments and which allowed sulfite ions to attack the apoprotein molecules. The mechanism of the sulfite action on the apoprotein is the breakdown of disulfide bonds in proteins, the disulfide bonds having important functions in the photoconversion process. From the present model experiments, it is suggested that the breakdown of disulfide bonds occurred and induced damage to the chloroplast lamellae or physiological functions in the SO/sub 2/-injured plant tissues. 17 references, 8 figures.

  2. Metabolizer in vivo of fullerenes and metallofullerenes by positron emission tomography

    Science.gov (United States)

    Li, Juan; Yang, Wenjiang; Cui, Rongli; Wang, Dongliang; Chang, Yanan; Gu, Weihong; Yin, Wenyan; Bai, Xue; Chen, Kui; Xia, Lin; Geng, Huan; Xing, Gengmei

    2016-04-01

    Fullerenes (C60) and metallofullerenes (Gd@C82) have similar chemical structure, but the bio-effects of both fullerene-based materials are distinct in vivo. Tracking organic carbon-based materials such as C60 and Gd@C82 is difficult in vivo due to the high content of carbon element in the living tissues themselves. In this study, the biodistribution and metabolism of fullerenes (C60 and Gd@C82) radiolabeled with 64Cu were observed by positron emission tomography (PET). 64Cu-C60 and 64Cu-Gd@C82 were prepared using 1, 4, 7, 10-tetrakis (carbamoylmethyl)-1, 4, 7, 10-tetra-azacyclodo-decanes grafted on carbon cages as a chelator for 64Cu, and were obtained rapidly with high radiochemical yield (≥90%). The new radio-conjugates were evaluated in vivo in the normal mouse model and tissue distribution by small animal PET/CT imaging and histology was carried out. The PET imaging, the biodistribution and the excretion of C60 and Gd@C82 indicated that C60 samples have higher blood retention and lower renal clearance than the Gd@C82 samples in vivo and suggested that the differences in metabolism and distribution in vivo were caused by the structural differences of the groups on the fullerene cages though there is chemical similarity between C60 and Gd@C82.

  3. Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation

    DEFF Research Database (Denmark)

    Supur, M.; Kawashima, Y.; Larsen, K. R.;

    2014-01-01

    ) obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6-311G(d,p) level, the orbital interactions between the crown ether moieties and the p surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation...... for 1 center dot Li+@C-60 and 2 center dot Li+@C-60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time-resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures...

  4. SOLUBILITY ENHANCEMENT OF POORLY WATER SOLUBLE DRUGS BY SOLID DISPERSIO

    Directory of Open Access Journals (Sweden)

    Amita Verm

    2012-01-01

    Full Text Available Solid dispersions have been employed to enhance the dissolution rates of poorly water-soluble drugs. Many approaches have been investigated for the preparation of solid dispersions. This paper reports the various solubility enhancement strategies in solid dispersion. The approaches described are fusion (melting, solvent evaporation, lyophilization (freeze drying, melt agglomeration process, extruding method, spray drying technology, use of surfactant, electro static spinning method and super critical fluid technology. This paper also highlights the potential applications and limitations of theseapproaches in solid dispersions.

  5. [Mutagen properties of water-soluble polysaccharides from Acorus calamus].

    Science.gov (United States)

    Gur'ev, A M; Belousov, M B; Akhmedzhanov, R R; Iusubov, M S; Voronova, O L; Karpova, G V; Churin, A A

    2010-08-01

    Mutagenic properties of water soluble polysaccharides (WSPS) extracted from Acorus calamus L. have been studied. Neither a single intravenous injection nor a course intraperitoneal introduction of WSPS in a dose of 1/2 LD50 to mice of the CBA/CaLac line increases the level of cytogenetic disorders in the bone marrow cells. The investigation of WSPS by means of the somatic mosaicism test showed that the given dose of WSPS does not increase the rate of mutant spots on Drosophila wings.

  6. Water-soluble constituents from aerial roots of Ficus microcarpa.

    Science.gov (United States)

    Ouyang, M-A; Kuo, Y-H

    2006-01-01

    Three new water-soluble constituents [ficuscarpanoside B (1), (7E,9Z)-dihydrophaseic acid 3-O-beta-D-glucopyranoside (4) and ficuscarpanic acid (6)] and the natural product 2,2'-dihydroxyl ether (7) have been isolated, together with three known compounds [(7S,8R)-syringoylglycerol (2), (7S,8R)-syringoylglycerol-7-O-beta-D-glucopyranoside (3) and icariside D2 (5)] from the aerial roots of Ficus microcarpa. Identification of their structures was achieved by 1D and 2D NMR experiments, including 1H-1H COSY, NOESY, HMQC and HMBC methods and FAB mass spectral data.

  7. Zwitterionic phosphorylcholine-protected water-soluble nanoparticles

    Institute of Scientific and Technical Information of China (English)

    JIN Qiao; LIU XiangSheng; XU JianPing; JI Jian; SHEN JiaCong

    2009-01-01

    The water-soluble Ag nanoparticles capped with novel zwitterionic thioalkylated phosphorylcholine were synthesized. The Ag nanoparticles showed remarkable stability in saline media with salt concen-trations as high as 2.0 mol/L and plasma using UV-vis absorption spectroscopy. Similarly, compared with tiopronin and citrate-protected Ag nanoparticles, the zwitterionic phosphorylcholine Ag nanopar-ticles did not precipitate out of solution when charged polyelectrolytes or biopolymers were added. The zwitterionic phosphorylcholine might be a better ligand for stabilizing metal nanoparticles.

  8. Zwitterionic phosphorylcholine-protected water-soluble Ag nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The water-soluble Ag nanoparticles capped with novel zwitterionic thioalkylated phosphorylcholine were synthesized.The Ag nanoparticles showed remarkable stability in saline media with salt concen-trations as high as 2.0 mol/L and plasma using UV-vis absorption spectroscopy.Similarly,compared with tiopronin and citrate-protected Ag nanoparticles,the zwitterionic phosphorylcholine Ag nanopar-ticles did not precipitate out of solution when charged polyelectrolytes or biopolymers were added.The zwitterionic phosphorylcholine might be a better ligand for stabilizing metal nanoparticles.

  9. Preparation and Properties of Water-soluble Conjugated Polyelectrolyte

    Institute of Scientific and Technical Information of China (English)

    BAO Xiangjun; HONG Ruibin; HU Jianhua; ZHONG Yiping; LIU Ping; DENG Wenji

    2014-01-01

    The water-soluble conjugated polyelectrolyte, poly[3-(1′-ethyloxy-2′-N- methylimidazole) thiophene] (PEOIMT), was prepared. Its photophysical and electrochemical properties, and response characteristics to the external condition (e g, temperature response, solvent response and pH response), were investigated. The results show the PEOIMT belongs to the organic semiconductor. The interaction between the PEOIMT and the bovine serum albumin (BSA) was investigated using UV-vis spectroscopy. It was found that the PEOIMT could interact with the BSA. The PEOIMT can be used as a biosensor to detect the BSA.

  10. The effects of C60(C(COOH)2)2-FITC on proliferation and differentiation of human mesenchymal stem cells in vitro.

    Science.gov (United States)

    Li, Juan; Song, Yan; Liu, Xiaoxiao; Zhang, Mingyi; He, Rui; Chang, Yanan; Jin, Junjiang; Xing, Geng-Mei; Zhang, Jun

    2013-10-01

    As manufactured nanoparticles, fullerene nanoparticles were used as the model to research the manufactured nanoparticles entering into cells and hence have been rapidly developed for biomedical uses. Human mesenchymal stem cells (hMSCs) have become the most widely used seeding cells in tissue engineering because they are readily obtained without ethical problems and are multipotent with regard to adipogenic, chondrogenic, and osteogenic lineages. Because of their favorable biological and cellular activities, C60 carboxyl derivatives are among the most widely studied C60 derivatives. FITC labeled C60(C(COOH)2)2 nanoparticles were charactered by FTIR, ESI-MS, XPS and DLS. The effects of C60(C(COOH)2)2-FITC on proliferation and differentiation of human mesenchymal stem cells (hMSCs) in vitro were observed. The fullerene nanoparticles are quickly internalized by the cells and they had low toxicity to proliferation of hMSCs. The C60(C(COOH)2)2 nanoparticles could promote cell proliferation, enhance osteoclast differentiation of hMSCs.

  11. Energetics and Electronic Structures of Inclusion Compounds of Large Fullerenes and Cycloparaphenylenes

    Science.gov (United States)

    Nagasawa, Yuya; Okada, Susumu

    2017-10-01

    The energetics and electronic structures of large fullerenes included within [n]cycloparaphenylenes ([n]CPPs) are investigated using density functional theory. We observe that the large fullerenes included within [n]CPP ([n]CPP ⊃ Cn, where n = 76 and 78) are energetically stable and the inclusion reactions are exothermic for the [n]CPP with a diameter of 1.49 nm or larger. Owing to the electronic states of the guest fullerene molecules and the host [n]CPP, [n]CPP ⊃ C60 possesses a staggered electronic structure near the energy gap between the highest occupied and lowest unoccupied states, leading to a narrower energy gap than that of fullerenes and CPP. We also demonstrate that the electron states associated with the fullerene exhibit an upward shift upon inclusion owing to the quantum confinement effect on the π states of fullerenes by the CPP.

  12. Time-efficient computation of the electronic structure of the C60 super-atom molecular orbital (SAMO) states in TDDFT

    Science.gov (United States)

    Mignolet, B.; Remacle, F.

    2016-12-01

    Fullerenes have a dense manifold of excited states composed of valence excited states and Rydberg states. Among Rydberg states, one distinguishes Super Atom Molecular Orbitals (SAMO), excited states in which an electron is promoted to a diffuse nanometer size molecular orbital with a hydrogenic-like character. Unlike typical Rydberg states, the electronic density of the SAMO states is mainly localized inside and in the close vicinity of the fullerene cage. In this proceeding, we propose a time-saving way to compute the electronic structure of the SAMO and Rydberg states of fullerenes at the TDDFT level by limiting the number of excitations allowed to build the excited states. We investigate the effect of limiting the number of excitations in C60 and compare it to the experimental binding energies. We also investigate the effect of the functional and basis set on the binding energies of the SAMO states.

  13. The formation of buckminsterfullerene (C$_{60}$) in interstellar space

    CERN Document Server

    Berné, Olivier

    2011-01-01

    Buckminsterfullerene (C$_{60}$) was recently confirmed to be the largest molecule identified in space. However, it remains unclear how, and where this molecule is formed. It is generally believed that C$_{60}$ is formed from the build up of small carbonaceous compounds, in the hot and dense envelopes of evolved stars. Analyzing infrared observations, obtained by Spitzer and Herschel, we found that C$_{60}$ is efficiently formed in the tenuous and cold environment of an interstellar cloud illuminated by strong ultraviolet (UV) radiation fields. This implies that another formation pathway, efficient at low densities, must exist. Based on recent laboratory and theoretical studies, we argue that Polycyclic Aromatic Hydrocarbons are converted into graphene, and subsequently C$_{60}$, under UV irradiation from massive stars. This shows that alternative - top-down - routes are key to understanding the organic inventory in space.

  14. Superintermolecular orbitals in the C60-pentacene complex

    Science.gov (United States)

    Zhang, G. P.; Gardner, A.; Latta, T.; Drake, K.; Bai, Y. H.

    2016-12-01

    We report a group of unusually big molecular orbitals in the C60-pentacene complex. Our first-principles density-functional calculation shows that these orbitals are very delocalized and cover both C60 and pentacene, which we call superintermolecular orbitals (SIMOs). Their spatial extension can reach 1 nm or larger. Optically, SIMOs are dark. Different from ordinary unoccupied molecular orbitals, SIMOs have a very weak Coulomb and exchange interaction. Their energy levels are very similar to the native superatomic molecular orbitals in C60and can be approximately characterized by orbital angular momentum quantum numbers. They have a distinctive spatial preference. These features fit the key characters of charge-generation states that channel initially bound electrons and holes into free-charge carriers. Thus, our finding is important for C60-pentacene photovoltaics.

  15. Charge transfer excitons in C60-dimers and polymers

    CERN Document Server

    Harigaya, K

    1996-01-01

    Charge-transfer (CT) exciton effects are investigated for the optical absorption spectra of crosslinked C60 systems by using the intermediate exciton theory. We consider the C60-dimers, and the two (and three) molecule systems of the C60-polymers. We use a tight-binding model with long-range Coulomb interactions among electrons, and the model is treated by the Hartree-Fock approximation followed by the single-excitation configuration interaction method. We discuss the variations in the optical spectra by changing the conjugation parameter between molecules. We find that the total CT-component increases in smaller conjugations, and saturates at the intermediate conjugations. It decreases in the large conjugations. We also find that the CT-components of the doped systems are smaller than those of the neutral systems, indicating that the electron-hole distance becomes shorter in the doped C60-polymers.

  16. Quantum Theory for Large Molecules $C_{60}$ Diffraction

    CERN Document Server

    Wu, Xiang-Yao; Liu, Xiao-Jing; Ba, Nuo; Wu, Yi-Heng; Tang, Hou-Li; Wang, Jing; Zhang, Si-Qi

    2011-01-01

    Diffraction phenomena of large molecules have been studied in many experiments, and these experiments are described by many theoretical works. In this paper, we study $C_{60}$ molecules single and double-slit diffraction with quantum theory approach, and we pay close attention to the $C_{60}$ diffraction experiment carried out by A.Zeilinger et.at in 1999. In double-slit diffraction, we consider the decoherence effect, and find the theoretical results are good agreement with experimental data.

  17. Superintermolecular orbitals in the C$_{60}$/pentacene complex

    OpenAIRE

    G.P. Zhang; Gardner, A.; Latta, T.; Drake, K.; Bai, Y. H.

    2016-01-01

    We report a group of unusually big molecular orbitals in the C60/pentacene complex. Our first-principles density functional calculation shows that these orbitals are very delocalized and cover both C60 and pentacene, which we call superintermolecular orbitals or SIMOs. Their spatial extension can reach 1 nm or larger. Optically, SIMOs are dark. Different from ordinary unoccupied molecular orbitals, SIMOs have a very weak Coulomb and exchange interaction. Their energy levels are very similar t...

  18. Enhanced superconductivity of fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Washington, II, Aaron L.; Teprovich, Joseph A.; Zidan, Ragaiy

    2017-06-20

    Methods for enhancing characteristics of superconductive fullerenes and devices incorporating the fullerenes are disclosed. Enhancements can include increase in the critical transition temperature at a constant magnetic field; the existence of a superconducting hysteresis over a changing magnetic field; a decrease in the stabilizing magnetic field required for the onset of superconductivity; and/or an increase in the stability of superconductivity over a large magnetic field. The enhancements can be brought about by transmitting electromagnetic radiation to the superconductive fullerene such that the electromagnetic radiation impinges on the fullerene with an energy that is greater than the band gap of the fullerene.

  19. Therapeutic Effects of Water Soluble Danshen Extracts on Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Yoon Hee Cho

    2013-01-01

    Full Text Available Danshen is a traditional Chinese medicine with many beneficial effects on cardiovascular diseases. The aim of this study was to evaluate the mechanisms responsible for the antiatherogenic effect of water soluble Danshen extracts (DEs. Rat vascular smooth muscle cells (VSMCs and human umbilical vein endothelial cells (HUVECs were treated with DE. To evaluate the effects of DE in vivo, carotid balloon injury and tail vein thrombosis were induced in Sprague-Dawley (SD rats and iliac artery stent was induced in New Zealand white rabbits. The inhibitory action of DE on platelet aggregation was confirmed with an impedance aggregometer. DE inhibited the production of reactive oxygen species, and the migration and proliferation of platelet-derived growth factor-BB stimulated VSMCs. Furthermore, DE prevented inflammation and apoptosis in HUVECs. Both effects of DE were reconfirmed in both rat models. DE treatment attenuated platelet aggregation in both in vivo and ex vivo conditions. Pretreatment with DE prevented tail vein thrombosis, which is normally induced by κ-carrageenan injection. Lastly, DE-treated rabbits showed decreased in-stent restenosis of stented iliac arteries. These results suggest that water soluble DE modulates key atherogenic events in VSMCs, endothelial cells, and platelets in both in vitro and in vivo conditions.

  20. p-Phosphonic acid calix[8]arene assisted dispersion and stabilisation of pea-pod C60@multi-walled carbon nanotubes in water.

    Science.gov (United States)

    Chen, Xianjue; Gibson, Christopher T; Britton, Joshua; Eggers, Paul K; Wahid, M Haniff; Raston, Colin L

    2015-02-11

    A facile approach has been developed for non-covalently stabilising pristine C60 and multi-walled carbon nanotubes (MWCNTs) in water in the presence of p-phosphonic acid calix[8]arene, along with the formation of a 'pea-pod' encapsulation of the fullerene inside the MWCNTs. Aqueous dispersions of the different carbon nano-materials are readily decorated with palladium nanoparticles.

  1. Fullerene Nanogears

    Science.gov (United States)

    1997-01-01

    The Numerical Aerospace Simulation Systems Division (NAS) of the NASA Ames Research Center, Moffett Field, California is conducting research into molecular-sized devices known as Nanotechnology. This photograph depicts two 'Fullerene Nano-gears' with multiple teeth. The hope is that one day, products can be constructed made of thousands of tiny machines that could self-repair and adapt to the environment in which they exist. Researchers have simulated attaching benzyne molecules to the outside of a nanotube to form gear teeth. Nanotubes are molecular-sized pipes made of carbon atoms. To 'drive' the gears, the supercomputer simulated a laser that served as a motor. The laser creates an electric field around the nanotube. A positively charged atom is placed on one side of the nanotube, and a negatively charged atom on the other side. The electric field drags the nanotube around like a shaft turning. Jie Han, Al Globus, Richard Jaffe and Glenn Deardorff are the authors of a technical paper detailing this technology which appears in The Journal of Nanotechnology.

  2. Fullerene-based one-dimensional crystalline nanopolymer formed through topochemical transformation of the parent nanowire

    DEFF Research Database (Denmark)

    Geng, Junfeng; Solov'yov, Ilia; Reid, David G.;

    2010-01-01

    Large-scale practical applications of fullerene (C_60) in nanodevices could be significantly facilitated if the commercially available micrometer-scale raw C_60 powder were further processed into a one-dimensional nanowire-related polymer displaying covalent bonding as molecular interlinks...... and resembling traditional important conjugated polymers. However, there has been little study thus far in this area despite the abundant literature on fullerene. Here we report the preparation and characterization of such a C_60-based polymer nanowire, (-C_60.TMB-)_n, where TMB=1,2,4-trimethylbenzene, which...... displays a well-defined crystalline nanostructure, exceptionally large length-to-width ratio and excellent thermal stability. The material is prepared by first growing the corresponding nanowire through a solution phase of C_60 followed by a topochemical polymerization reaction in the solid state. Gas...

  3. Machine Phase Fullerene Nanotechnology: 1996

    Science.gov (United States)

    Globus, Al; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    NASA has used exotic materials for spacecraft and experimental aircraft to good effect for many decades. In spite of many advances, transportation to space still costs about $10,000 per pound. Drexler has proposed a hypothetical nanotechnology based on diamond and investigated the properties of such molecular systems. These studies and others suggest enormous potential for aerospace systems. Unfortunately, methods to realize diamonoid nanotechnology are at best highly speculative. Recent computational efforts at NASA Ames Research Center and computation and experiment elsewhere suggest that a nanotechnology of machine phase functionalized fullerenes may be synthetically relatively accessible and of great aerospace interest. Machine phase materials are (hypothetical) materials consisting entirely or in large part of microscopic machines. In a sense, most living matter fits this definition. To begin investigation of fullerene nanotechnology, we used molecular dynamics to study the properties of carbon nanotube based gears and gear/shaft configurations. Experiments on C60 and quantum calculations suggest that benzyne may react with carbon nanotubes to form gear teeth. Han has computationally demonstrated that molecular gears fashioned from (14,0) single-walled carbon nanotubes and benzyne teeth should operate well at 50-100 gigahertz. Results suggest that rotation can be converted to rotating or linear motion, and linear motion may be converted into rotation. Preliminary results suggest that these mechanical systems can be cooled by a helium atmosphere. Furthermore, Deepak has successfully simulated using helical electric fields generated by a laser to power fullerene gears once a positive and negative charge have been added to form a dipole. Even with mechanical motion, cooling, and power; creating a viable nanotechnology requires support structures, computer control, a system architecture, a variety of components, and some approach to manufacture. Additional

  4. An Infrared Study of Fullerene Planetary Nebulae

    CERN Document Server

    Garcia-Hernandez, D A; Garcia-Lario, P; Acosta-Pulido, J A; Manchado, A; Stanghellini, L; Shaw, R A; Cataldo, F

    2012-01-01

    We present a study of 16 PNe where fullerenes have been detected in their Spitzer spectra. This large sample of objects offers an unique opportunity to test conditions of fullerene formation and survival under different metallicity environments as we are analyzing five sources in our own Galaxy, four in the LMC, and seven in the SMC. Among the 16 PNe under study, we present the first detection of C60 (possibly also C70) fullerenes in the PN M 1-60 as well as of the unusual 6.6, 9.8, and 20 um features (possible planar C24) in the PN K 3-54. Although selection effects in the original samples of PNe observed with Spitzer may play a potentially significant role in the statistics, we find that the detection rate of fullerenes in C-rich PNe increases with decreasing metallicity (5% in the Galaxy, 20% in the LMC, and 44% in the SMC). CLOUDY photoionization modeling matches the observed IR fluxes with central stars that display a rather narrow range in effective temperature (30,000-45,000 K), suggesting a common evo...

  5. Polyhydroxy fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Georgieva, Angelina T., E-mail: angelinageorgieva2009@gmail.com [University of Florida, Department of Materials Science and Engineering, Particle Engineering Research Center (United States); Pappu, Vijay [University of Florida, Center for Applied Optimization (United States); Krishna, Vijay [University of Florida, Department of Materials Science and Engineering, Particle Engineering Research Center (United States); Georgiev, Pando G. [University of Florida, Center for Applied Optimization (United States); Ghiviriga, Ion [University of Florida, NMR Facility, Department of Chemistry (United States); Indeglia, Paul [Agency for Sustainable Systems in Science and Technology, Inc. (United States); Xu, Xin; Fan, Z. Hugh [University of Florida, Department of Mechanical and Aerospace Engineering (United States); Koopman, Ben [University of Florida, Department of Environmental Engineering Sciences (United States); Pardalos, Panos M. [University of Florida, Center for Applied Optimization (United States); Moudgil, Brij [University of Florida, Department of Materials Science and Engineering, Particle Engineering Research Center (United States)

    2013-07-15

    Characterization of C{sub 60} polyhydroxyfullerenes (PHF) prepared in alkaline media, preparation facilitated by phase-transfer catalyst, presents challenges in determining the chemical structure resulting from the possibility of multiple isomers or analogs with greater or fewer hydroxyl groups from a single reaction mixture. This paper presents the utilization of analytical methods employed in tandem, especially X-ray photoelectron spectroscopy, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy for semi-quantitative analysis on the number of hydroxyl groups present in PHF. Capillary Electrophoresis was used for purity estimation of the material. Multiple spectra and electropherograms were analyzed using a new simultaneous curve fitting method. The most accurate estimate of hydroxyl groups for C{sub 60} polyhydroxy fullerenes obtained is between 16 and 18 allylic hydroxyl groups by combining analytical methods' results with 5 % accuracy. High precision (reproducibility) of the experiments is observed. Purity of 98 % is estimated by capillary electrophoresis. The size of PHF nanoparticles or aggregates has been determined by atomic force microscopy to be 7.4-14.2 nm. According to the elemental analysis the average probable empirical formula for the most pure PHF at pH 7.1 is C{sub 60}O{sub 17}H{sub 12}Na{sub 5}(NaHCO{sub 3}){sub 3}(H{sub 2}O){sub 13} and the average formula weight is 1,605.9 g/mol. This is the first thorough characterization of PHF in terms of purity.

  6. A search of diffuse bands in fullerene planetary nebulae: evidence for diffuse circumstellar bands

    CERN Document Server

    Diaz-Luis, J J; Rao, N Kameswara; Manchado, A; Cataldo, F

    2014-01-01

    Large fullerenes and fullerene-based molecules have been proposed as carriers of diffuse interstellar bands (DIBs). The recent detection of the most common fullerenes (C60 and C70) around some Planetary Nebulae (PNe) now enable us to study the DIBs towards fullerene-rich space environments. We search DIBs in the optical spectra towards three fullerene-containing PNe (Tc 1, M 1-20, and IC 418). Special attention is given to DIBs which are found to be unusually intense towards these fullerene sources. In particular, an unusually strong 4428A absorption feature is a common charateristic to fullerene PNe. Similarly to Tc 1, the strongest optical bands of neutral C60 are not detected towards IC 418. Our high-quality (S/N > 300) spectra for PN Tc 1 together with its large radial velocity permits us to search for the presence of diffuse bands of circumstellar origin which we refer to as diffuse circumstellar bands (DCBs). We report the first tentative detection of two DCBs at 4428 and 5780 A in the fullerene-rich ci...

  7. Fluorescence characteristics of water soluble organic carbon in eastern China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Fluorescence excitation and average molecular weight of 46 water soluble organic matter (WSOC) samples extracted from 20 soil types in eastern China were determined. It was found all samples shared similar spectroscopy. A good linear relationship existed between total organic carbon and excitation in the range of 350 to 450 nm though the content of organic carbon and pH of the samples vary in a wide range. No significant correlation between relative excitation intensity and average molecular weight of WSOC and FA was found, but the partial correlation became significant with pH as the controlling factor for WSOC samples. The relative excitation intensity showed a general trend of increasing from south to north in the study area. The pH value might play an important role in regulating the fluorescent spatial variation of WSOC.

  8. Interaction of water-soluble bridged porphyrin with DNA

    Institute of Scientific and Technical Information of China (English)

    Kai WANG; Zhi ZHANG; Qianni GUO; Xiaoping BAO; Zaoying LI

    2008-01-01

    A water-soluble porphyrin dimer (Por Dimer) containing eight positive charges, bridged by 4,4'-dicarboxy-2,2'-bipyridine, has been synthesized. With Meso-tetrakis(N-methyl-pyridium-4-yl)porphyrin (H2TMPyP) as the reference compound, the water-sol-uble porphyrin dimer was investigated for its inter-action with DNA by absorption, fluorescence, and circular dichroism (CD) spectroscopy. The apparent affinity binding constant (Kapp= 1.2×106) of Por Dimer binding to CT DNA was measured by a com-petition method with ethidium bromide (EB) (that of H2TMPyP was 6.9×106). The cleavage ability of Por Dimer to pBR322 plasmid DNA was studied by gel electrophoresis. The results suggest that the binding modes of Por Dimer were complex and involve both intercalation and outside binding.

  9. Preparation of water soluble chitosan by hydrolysis using hydrogen peroxide.

    Science.gov (United States)

    Xia, Zhenqiang; Wu, Shengjun; Chen, Jinhua

    2013-08-01

    Chitosan is not soluble in water, which limits its wide application particularly in the medicine and food industry. In the present study, water soluble chitosan (WSC) was prepared by hydrolyzing chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid in homogeneous phase. Factors affecting hydrolysis were investigated and the optimal hydrolysis conditions were determined. The WSC structure was characterized by Fourier transform infrared spectroscopy. The resulting products were composed of chitooligosaccharides of DP 2-9. The WSC content of the product and the yield were 94.7% and 92.3% (w/w), respectively. The results indicate that WSC can be effectively prepared by hydrolysis of chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid.

  10. Reactivity of Metal Ions Bound to Water-Soluble Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Sauer, N.N.; Watkins, J.G.; Lin, M.; Birnbaum, E.R.; Robison, T.W.; Smith, B.F.; Gohdes, J.W.; McDonald, J.G.

    1999-06-29

    The intent of this work is to determine the effectiveness of catalysts covalently bound to polymers and to understand the consequences of supporting the catalysts on catalyst efficiency and selectivity. Rhodium phosphine complexes with functional groups for coupling to polymers were prepared. These catalyst precursors were characterized using standard techniques including IR, NMR, and elemental analysis. Studies on the modified catalysts showed that they were still active hydrogenation catalysts. However, tethering of the catalysts to polyamines gave systems with low hydrogenation activity. Analogous biphasic systems were also explored. Phosphine ligands with a surfactant-like structure have been synthesized and used to prepare catalytically active complexes of palladium. The palladium complexes were utilized in Heck-type coupling reactions (e.g. coupling of iodobenzene and ethyl acrylate to produce ethyl cinnamate) under vigorously stirred biphasic reaction conditions, and were found to offer superior performance over a standard water-soluble palladium catalyst under analogous conditions.

  11. Water Soluble Fluorescent Carbon Nanodots from Biosource for Cells Imaging

    Directory of Open Access Journals (Sweden)

    Kumud Malika Tripathi

    2017-01-01

    Full Text Available Carbon nanodots (CNDs derived from a green precursor, kidney beans, was synthesized with high yield via a facile pyrolysis technique. The CND material was easily modified through simple oxidative treatment with nitric acid, leading to a high density “self-passivated” water soluble form (wsCNDs. The synthesized wsCNDs have been extensively characterized by using various microscopic and spectroscopic techniques and were crystalline in nature. The highly carboxylated wsCNDs possessed tunable-photoluminescence emission behavior throughout the visible region of the spectrum, demonstrating their application for multicolor cellular imaging of HeLa cells. The tunable-photoluminescence properties of “self-passivated” wsCNDs make them a promising candidate as a probe in biological cell-imaging applications.

  12. Drug delivery by water-soluble organometallic cages.

    Science.gov (United States)

    Therrien, Bruno

    2012-01-01

    Until recently, organometallic derivatives were generally viewed as moisture- and air-sensitive compounds, and consequently very challenging to synthesise and very demanding in terms of laboratory requirements (Schlenk techniques, dried solvent, glove box). However, an increasing number of stable, water-soluble organometallic compounds are now available, and organometallic chemistry in aqueous phase is a flourishing area of research. As such, coordination-driven self-assemblies using organometallic building blocks are compatible with water, thus opening new perspectives in bio-organometallic chemistry.This chapter gives a short history of coordination-driven self-assembly, with a special attention to organometallic metalla-cycles, especially those composed of half-sandwich complexes. These metalla-assemblies have been used as sensors, as anticancer agents, as well as drug carriers.

  13. Drug delivery strategies for poorly water-soluble drugs.

    Science.gov (United States)

    Fahr, Alfred; Liu, Xiangli

    2007-07-01

    The drug candidates coming from combinatorial chemistry research and/or the drugs selected from biologically based high-throughput screening are quite often very lipophilic, as these drug candidates exert their pharmacological action at or in biological membranes or membrane-associated proteins. This challenges drug delivery institutions in industry or academia to develop carrier systems for the optimal oral and parenteral administration of these drugs. To mention only a few of the challenges for this class of drugs: their oral bioavailability is poor and highly variable, and carrier development for parenteral administration is faced with problems, including the massive use of surface-active excipients for solubilisation. Formulation specialists are confronted with an even higher level of difficulties when these drugs have to be delivered site specifically. This article addresses the emerging formulation designs for delivering of poorly water-soluble drugs.

  14. Facile synthesis of water-soluble curcumin nanocrystals

    Directory of Open Access Journals (Sweden)

    Marković Zoran M.

    2015-01-01

    Full Text Available In this paper, facile synthesis of water soluble curcumin nanocrystals is reported. Solvent exchange method was applied to synthesize curcumin nanocrystals. Different techniques were used to characterize the structural and photophysical properties of curcumin nanocrystals. We found that nanocurcumin prepared by this method had good chemical and physical stability, could be stored in the powder form at room temperature, and was freely dispersible in water. It was established that the size of curcumin nanocrystals was varied in the range of 20-500 nm. Fourier transform infrared spectroscopy and UV-Vis analyses showed the presence of tetrahydrofuran inside the curcumin nanocrystals. Also, it was found that nanocurcumin emitted photoluminescencewith yellow-green colour. [Projekat Ministarstva nauke Republike Srbije, br. 172003

  15. Nucleation of C60 on ultrathin SiO2

    Science.gov (United States)

    Conrad, Brad; Groce, Michelle; Cullen, William; Pimpinelli, Alberto; Williams, Ellen; Einstein, Ted

    2012-02-01

    We utilize scanning tunneling microscopy to characterize the nucleation, growth, and morphology of C60 on ultrathin SiO2 grown at room temperature. C60 thin films are deposited in situ by physical vapor deposition with thicknesses varying from <0.05 to ˜1 ML. Island size and capture zone distributions are examined for a varied flux rate and substrate deposition temperature. The C60 critical nucleus size is observed to change between monomers and dimers non-monotonically from 300 K to 500 K. Results will be discussed in terms of recent capture zone studies and analysis methods. Relation to device fabrication will be discussed. doi:10.1016/j.susc.2011.08.020

  16. Physical properties of highly-oriented rhombohedral C60 polymer

    Science.gov (United States)

    Tokumoto, M.; Narymbetov, B.; Kobayashi, H.; Makarova, T. L.; Davydov, V. A.; Rakhmania, A. V.; Kashevarova, L. S.

    2000-11-01

    Rhombohedral phase of pressure-temperature treated C60 polymer was investigated by resistivity, X-ray diffraction and ESR measurements. The pure rhombohedral phase of C60 polymer displays highly anisotropic electrical properties, and the conductivity in the polymerized 2D plane exhibits a metallic feature with weak localization. X-ray diffraction measurements have revealed that the diffraction patterns are essentially anisotropic. We have carried out the scanning of a reciprocal space in order to reveal the distribution of diffraction intensities. The result testifies to the high degree of mutual orientations of crystallites in the sample not only along the [001] direction but also in the (001) plane. Apparently the observed mosaicity of the crystal is connected with the highly anisotropic electrical properties of the rhombohedral phase of pressure-treated C60 polymer. A Dysonian ESR absorption lineshape consistent with the metallic nature was observed.

  17. Pristine fullerenes mixed by vacuum-free solution process: Efficient electron transport layer for planar perovskite solar cells

    Science.gov (United States)

    Dai, Si-Min; Tian, Han-Rui; Zhang, Mei-Lin; Xing, Zhou; Wang, Lu-Yao; Wang, Xin; Wang, Tan; Deng, Lin-Long; Xie, Su-Yuan; Huang, Rong-Bin; Zheng, Lan-Sun

    2017-01-01

    Discovery of organic-inorganic hybrid perovskites ignites the dream of next-generation solar cells fabricated by low-cost solution processing. To date, fullerene derivative [6,6]-phenyl-C61- butyric acid methyl ester (PC61BM), is the most prevalently used electron transport layer for high efficiency p-i-n planar heterojunction perovskite solar cells. Compared with PC61BM, pristine fullerenes, such as C60 and C70, have shown superiority of higher electron mobility and much lower costs. Due to the poor solubility and strong tendency to crystallize for pristine fullerenes in solution process, it is still a challenge to deposit compact and continuous film of pristine fullerenes for p-i-n type perovskite solar cells by solution processing. Herein, solution processed pristine fullerenes (C60 and C70) were used as electron transport layers to replace PC61BM in perovskite solar cells with high performance and enhanced stability. Power conversion efficiency of 14.04% was obtained by using mixture of C60 and C70 as electron transport layer, which is comparable to that of PC61BM based device (13.74%). We demonstrated that the strong tendency of pristine fullerenes to crystallize during solvent removal can be largely mitigated by mixing different kinds of pristine fullerenes. These findings implicate pristine fullerenes as promising electron transport layers for high performance perovskite solar cells.

  18. Water-soluble polymers for recovery of metal ions from aqueous streams

    Science.gov (United States)

    Smith, Barbara F.; Robison, Thomas W.

    1998-01-01

    A process of selectively separating a target metal contained in an aqueous solution by contacting the aqueous solution containing a target metal with an aqueous solution including a water-soluble polymer capable of binding with the target metal for sufficient time whereby a water-soluble polymer-target metal complex is formed, and, separating the solution including the water-soluble polymer-target metal complex from the solution is disclosed.

  19. A Novel Injectable Water-Soluble Amphotericin B-Arabinogalactan Conjugate

    OpenAIRE

    Falk, Rama; Domb, Abraham J.; Polacheck, Itzhack

    1999-01-01

    New, stable, highly water-soluble, nontoxic polysaccharide conjugates of amphotericin B (AmB) are described. AmB was conjugated by a Schiff-base reaction with oxidized arabinogalactan (AG). AG is a highly branched natural polysaccharide with unusual water solubility (70% in water). A high yield of active AmB was obtained with the conjugates which were similarly highly water soluble and which could be appropriately formulated for injection. They showed comparable MICs for Candida albicans and ...

  20. Fragmentation Mechanism of Fullerenes in the Positive and Negative Ion Channels

    Institute of Scientific and Technical Information of China (English)

    孔庆宇; 赵利; 庄军; 钱士雄; 李郁芬

    2001-01-01

    We have performed the photofragmentation studies of pristine C60 and C60/C70 composites on the reflectron time-of-flight mass spectrometer (RTOF MS) in the positive and negative ion channels. The mechanism of the formation of daughter fullerenes in the negative ion channel and the enhancement of fullerene coalescence reactions have been discussed and compared to our previous studies on the linear TOF. The 5 cm free expansion path in the RTOF experiments provides sufficient time and a favourable environment for the electrons to attach to the neutral daughter species, so it is thought to play a key role for the appearance of strong mass peaks of anionic fragmentation and aggregation fullerene products. The appearance of odd-numbered "fullerene" fragments is briefly discussed.

  1. Structure and dynamics of C60 molecules on Au(111)

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Heekeun [Penn State University; Schwarze, A [Penn State University; Diehl, R D [Penn State University; Pussi, K [Lappeenranta University of Technology; Colombier, A [Universite de Lorraine; Gaudry, E. [Universite de Lorraine; Ledieu, J [Universite de Lorraine; McGuirk, G M [Universite de Lorraine; Serkovic Loli, L N [Universite de Lorraine; Fournee, V [Universite de Lorraine; Wang, Lin-Lin [Ames Laboratory; Schull, G [Universite de Strasbourg; Berndt, R [Christian-Albrechts-Universitt zu Kiel

    2014-06-01

    Earlier studies of C60 adsorption on Au(111) reported many interesting and complex features. We have performed coordinated low-energy electron diffraction, scanning tunneling microscopy (STM), and density functional theory studies to elucidate some of the details of the monolayer commensurate (2√3 × 2√3)R30° phase. We have identified the adsorption geometries of the two states that image as dim and bright in STM. These consist of a C60 molecule with a hexagon side down in a vacancy (hex-vac) and a C60 molecule with a carbon-carbon 6:6 bond down on a top site (6:6-top), respectively. We have studied the detailed geometries of these states and find that there is little distortion of the C60 molecules, but there is a rearrangement of the substrate near the C60 molecules. The two types of molecules differ in height, by about 0.7 Å, which accounts for most of the difference in their contrast in the STM images. The monolayer displays dynamical behavior, in which the molecules flip from bright to dim, and vice versa. We interpret this flipping as the result of the diffusion of vacancies in the surface layers of the substrate. Our measurements of the dynamics of this flipping from one state to the other indicate that the activation energy is 0.66 ± 0.03 eV for flips that involve nearest-neighbor C60 molecules, and 0.93 ± 0.03 for more distant flips. Based on calculated activation energies for vacancies diffusing in Au, we interpret these to be a result of surface vacancy diffusion and bulk vacancy diffusion. These results are compared to the similar system of Ag(111)-(2√3 × 2√3)R30°-C60. In both systems, the formation of the commensurate C60 monolayer produces a large number of vacancies in the top substrate layer that are highly mobile, effectively melting the interfacial metal layer at temperatures well below their normal melting temperatures.

  2. The Structure and Mechanical Properties of C60 Fullerite

    Directory of Open Access Journals (Sweden)

    S.O. Rudchenko

    2014-01-01

    Full Text Available The fullerite films with texture (110 were prepared by the condensation of C60 molecules on KCl, LiF, and Si substrates. The hardness (Н  0,42 GPa and Young’s modulus (Е  14,1 GPa of the fullerite films were determined by nanoindentation method at continuous scanning in depth. The results were compared with theoretical estimates of elastic modules and previous works on measurements of elastic characteristics and hardness of crystalline C60.

  3. Fabrication and electrochemical properties of insoluble fullerene-diamine adduct thin-films as buffer layer by alternate immersion process

    Science.gov (United States)

    Saito, Jo; Akiyama, Tsuyoshi; Suzuki, Atsushi; Oku, Takeo

    2017-01-01

    Insoluble fullerene-diamine adduct thin-films consisting of C60 and 1,2-diaminoethane were easily fabricated on an electrode by an alternate immersion process. Formation of the C60-diamine adduct films were confirmed using transmission absorption spectroscopy and atomic force microscopy. An inverted-type organic solar cells were fabricated by using the C60-diamine adduct film as the electron transport layer. The resultant photoelectric conversation performance of the solar cells suggested that photocurrent is generated via the photoexcitation of polythiophene. The result suggests that the present insoluble fullerene-diamine adduct films worked as buffer layer for organic thin-film solar cells.

  4. Deposition of matrix-free fullerene films with improved morphology by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren;

    2013-01-01

    Thin films of C60 were deposited by matrix-assisted pulsed laser evaporation (MAPLE) from a frozen target of anisole with 0.67 wt% C60. Above a fluence of 1.5 J/cm2 the C60 films are strongly non-uniform and are resulting from transfer of matrix-droplets containing fullerenes. At low fluence...... the fullerene molecules in the films are intact, the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the film. This may indicate a regime of dominant evaporation at low fluence which merges into the MAPLE regime of liquid ejection of the host matrix...

  5. Morphology of nested fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Srolovitz, D.J.; Safran, S.A.; Homyonfer, M.; Tenne, R. (Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100 (Israel))

    1995-03-06

    We introduce a continuum model which shows that dislocations and/or grain boundaries are intrinsic features of nested fullerenes whose thickness exceeds a critical value to relieve the large inherent strains in these structures. The ratio of the thickness to the radius of the nested fullerenes is determined by the ratio of the surface to curvature and dislocation (or grain boundary) energies. Confirming experimental evidence is presented for nested fullerenes with small thicknesses and with spherosymmetric shapes.

  6. Investigation of optical limiting in C60 solution

    Science.gov (United States)

    Joshi, M. P.; Mishra, S. R.; Rawat, H. S.; Mehendale, S. C.; Rustagi, K. C.

    1993-04-01

    Experimental and theoretical studies of optical limiting for 30 ns pulses at 527 nm in C60 are reported. The results indicate that the optical limiting action may involve contribution from other nonlinear loss mechanisms in addition to increased absorption from the photoexcited triplet state.

  7. Preparation of photovoltaic cells from sexithiophene-C-60 blends

    NARCIS (Netherlands)

    Veenstra, SC; Malliaras, GG; Brouwer, HJ; Esselink, FJ; Krasnikov, VV; vanHutten, PF; Wildeman, J; Jonkman, HT; Sawatzky, GA; Hadziioannou, G; Mohlmann, GR

    1996-01-01

    Large photovoltaic responses have been recently observed in devices based on conjugated polymer-C-60 blends. Their enhanced performance, which relies on the formation of a bicontinuous network of donor-acceptor heterojunctions, is very sensitive to the morphology of the blend. In this paper, we prop

  8. Electric Current Induced Light Emission from C60

    NARCIS (Netherlands)

    Palstra, T.T.M.; Haddon, R.C.; Lyons, K.B.

    1997-01-01

    We report the luminescence of C60 crystals and films due to the passage of an electrical current. The current-voltage behavior is highly non-linear with light-emission beyond a threshold voltage. The emission spectrum is featureless and resembles black-body radiation with an effective temperature on

  9. Dynamics and phase transitions in A 1C 60 compounds

    Science.gov (United States)

    Schober, H.; Renker, B.; Heid, R.; Tölle, A.

    1997-02-01

    We present an overview of extensive inelastic neutron scattering experiments carried out on powders of A 1C 60. The various phases leave strong fingerprints in the microscopic dynamics confirming the solid-state chemical reactions. The strong kinetic phase transitions can be followed in real time and turn out to be highly complex.

  10. IR-REMPI spectroscopy for thermometry of C-60

    NARCIS (Netherlands)

    van Heijnsbergen, D.; von Helden, G.; Sartakov, B.; Meijer, G.

    2000-01-01

    Gas-phase C-60 molecules are excited with a 30 ps 266 nm Nd:YAG laser, followed by a train of high-power infrared (IR) sub-picosecond pulses from a free electron laser (FEL), which resonantly heats the molecules up to internal energies at which they efficiently undergo delayed ionization. By tuning

  11. Electrical conductivity of nanostructured and C60-modified aluminum

    NARCIS (Netherlands)

    Zameshin, A.; Popov, M.; Medvedev, V.V.; Perfilov, S.; Lomakin, R.; Buga, S.; Denisov, V.; Kirichenko, A.; Skryleva, E.; Tatyanin, E.; Aksenenkov, V.; Blank, V.

    2012-01-01

    In this paper, we study the electrical conductivity of nanostructured C60-modified aluminum, and the possibility of optimizing its electrical and mechanical properties. The model proposed allows estimating the electrical conductivity of the material at low surface filling factor. A number of samples

  12. Electrical conductivity of nanostructured and C-60-modified aluminum

    NARCIS (Netherlands)

    Zameshin, A.; Popov, M.; Medvedev, V.; Perfilov, S.; Lomakin, R.; Buga, S.; Denisov, V.; Kirichenko, A.; Skryleva, E.; Tatyanin, E.; Aksenenkov, V.; Blank, V.

    2012-01-01

    In this paper, we study the electrical conductivity of nanostructured C-60-modified aluminum, and the possibility of optimizing its electrical and mechanical properties. The model proposed allows estimating the electrical conductivity of the material at low surface filling factor. A number of sample

  13. Shock-wave processing of C60 in hydrogen

    Science.gov (United States)

    Biennier, L.; Jayaram, V.; Suas-David, N.; Georges, R.; Singh, M. Kiran; Arunan, E.; Kassi, S.; Dartois, E.; Reddy, K. P. J.

    2017-02-01

    Context. Interstellar carbonaceous particles and molecules are subject to intense shocks in astrophysical environments. Shocks induce a rapid raise in temperature and density which strongly affects the chemical and physical properties of both the gas and solid phases of the interstellar matter. Aims: The shock-induced thermal processing of C60 particles in hydrogen has been investigated in the laboratory under controlled conditions up to 3900 K with the help of a material shock-tube. Methods: The solid residues generated by the exposure of a C60/H2 mixture to a millisecond shock wave were collected and analyzed using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman micro-spectroscopy, and infrared micro-spectroscopy. The gaseous products were analyzed by Gas Chromatography and Cavity Ring Down Spectroscopy. Results: Volatile end-products appear above reflected shock gas temperatures of 2540 K and reveal the substantial presence of small molecules with one or two C atoms. These observations confirm the role played by the C2 radical as a major product of C60 fragmentation and less expectedly highlight the existence of a single C atom loss channel. Molecules with more than two carbon atoms are not observed in the post-shock gas. The analysis of the solid component shows that C60 particles are rapidly converted into amorphous carbon with a number of aliphatic bridges. Conclusions: The absence of aromatic CH stretches on the IR spectra indicates that H atoms do not link directly to aromatic cycles. The fast thermal processing of C60 in H2 over the 800-3400 K temperature range leads to amorphous carbon. The analysis hints at a collapse of the cage with the formation of a few aliphatic connections. A low amount of hydrogen is incorporated into the carbon material. This work extends the range of applications of shock tubes to studies of astrophysical interest.

  14. C60 and Sc3N@C80(TMB-PPO derivatives as constituents of singlet oxygen generating, thiol-ene polymer nanocomposites

    Directory of Open Access Journals (Sweden)

    Ashli R. Toles

    2016-07-01

    Full Text Available Numerous functionalization methods have been employed to increase the solubility, and therefore, the processability of fullerenes in composite structures, and of these radical addition reactions continue to be an important methodology. C60 and Sc3N@C80 derivatives were prepared via radical addition of the photodecomposition products from the commercial photoinitiator TMB-PPO, yielding C60(TMB-PPO5 and Sc3N@C80(TMB-PPO3 as preferred soluble derivatives obtained in high yields. Characterization of the mixture of isomers using standard techniques suggests an overall 1PPO:6TMB ratio of addends, reflecting the increased reactivity of the carbon radical. Although, a higher percentage of PPO is observed in the Sc3N@C80(TMB-PPO3 population, perhaps due to reverse electronic requirements of the substrate. Visually dispersed thiol-ene nanocomposites with low extractables were prepared using two monomer compositions (PETMP:TTT and TMPMP:TMPDE with increasing fullerene derivative loading to probe network structure-property relationships. Thermal stability of the derivatives and the resulting networks decreased with increased functionality and at high fullerene loadings, respectively. TMPMP:TMPDE composite networks show well-dispersed derivatives via TEM imaging, and increasing Tg’s with fullerene loading, as expected for the incorporation of a more rigid network component. PETMP:TTT composites show phase separation in TEM, which is supported by the observed Tg’s. Singlet oxygen generation of the derivatives decreases with increased functionality; however, this is compensated for by the tremendous increase in solubility in organic solvents and miscibility with monomers. Most importantly, singlet oxygen generation from the composites increased with fullerene derivative loading, with good photostability of the networks.

  15. Histopathology of fathead minnow (Pimephales promelas) exposed to hydroxylated fullerenes.

    Science.gov (United States)

    Jovanović, Boris; Whitley, Elizabeth M; Palić, Dušan

    2014-11-01

    Hydroxylated fullerenes are reported to be very strong antioxidants, acting to quench reactive oxygen species, thus having strong potential for important and widespread applications in innovative therapies for a variety of disease processes. However, their potential for toxicological side effects is still largely controversial and unknown. Effects of hydroxylated fullerenes C60(OH)24 on the fathead minnow (Pimephales promelas) were investigated microscopically after a 72-hour (acute) exposure by intraperitoneal injection of 20 ppm of hydroxylated fullerenes per gram of body mass. Cumulative, semi-quantitative histopathologic evaluation of brain, liver, anterior kidney, posterior kidney, skin, coelom, gills and the vestibuloauditory system revealed significant differences between control and hydroxylated fullerene-treated fish. Fullerene-treated fish had much higher cumulative histopathology scores. Histopathologic changes included loss of cellularity in the interstitium of the kidney, a primary site of haematopoiesis in fish, and loss of intracytoplasmic glycogen in liver. In the coelom, variable numbers of leukocytes, including many macrophages and fewer heterophils and rodlet cells, were admixed with the nanomaterial. These findings raise concern about in vivo administration of hydroxylated fullerenes in experimental drugs and procedures in human medicine, and should be investigated in more detail.

  16. Metal Evaporation-Induced Degradation of Fullerene Acceptors in Polymer/Fullerene Solar Cells.

    Science.gov (United States)

    Huang, Wenchao; Gann, Eliot; Thomsen, Lars; Tadich, Anton; Cheng, Yi-Bing; McNeill, Christopher R

    2016-01-27

    Surface-sensitive NEXAFS spectroscopy is used to probe the interaction between low work function metal electrodes and fullerene derivatives in organic solar cells. Evaporation of either Ca or Al electrodes onto films of the fullerene derivatives (6,6)-phenyl-C61-butyric acid methyl ester (PCBM) and indene-C60 bisadduct (ICBA) leads to a dramatic change in the observed NEXAFS spectrum. The observed changes cannot be explained only in terms of interfacial electronic doping or charge transfer, but rather point to the formation of new chemical bonds that destroy the extensive electron delocalization on the C60 cage. A combination of ex situ and in situ ultrahigh vacuum measurements indicates that metal evaporation results in a change in the electronic structure of PCBM that then facilitates chemical degradation and oxidation in the presence of oxygen. To investigate the effect of this chemical interaction on device performance, a unique transfer method to laminate the Al electrode to the top of polymer blend is used, in which case, the chemical degradation of the fullerene is not observed. Device performance of P3HT/PCBM blend solar cells in which the top metal electrode has either been thermally evaporated or transferred is then compared. These results highlight that chemical, as well as electronic, interactions between metals and organic semiconductors must be considered.

  17. Packing and Disorder in Substituted Fullerenes

    KAUST Repository

    Tummala, Naga Rajesh

    2016-07-15

    Fullerenes are ubiquitous as electron-acceptor and electron-transport materials in organic solar cells. Recent synthetic strategies to improve the solubility and electronic characteristics of these molecules have translated into a tremendous increase in the variety of derivatives employed in these applications. Here, we use molecular dynamics (MD) simulations to examine the impact of going from mono-adducts to bis- and tris-adducts on the structural, cohesive, and packing characteristics of [6,6]-phenyl-C60-butyric acid methyl ester (PCBM) and indene-C60. The packing configurations obtained at the MD level then serve as input for density functional theory calculations that examine the solid-state energetic disorder (distribution of site energies) as a function of chemical substitution. The variations in structural and site-energy disorders reflect the fundamental materials differences among the derivatives and impact the performance of these materials in thin-film electronic devices.

  18. Thermodynamics of hydration of fullerols [C60(OH)n] and hydrogen bond dynamics in their hydration shells

    Science.gov (United States)

    Keshri, Sonanki; Tembe, B. L.

    2017-02-01

    Molecular dynamics simulations of fullerene and fullerols [C60(OH)n, where n = 2-30] in aqueous solutions have been performed for the purpose of obtaining a detailed understanding of the structural and dynamic properties of these nanoparticles in water. The structures, dynamics and hydration free energies of the solute molecules in water have been analysed. Radial distribution functions, spatial density distribution functions and hydrogen bond analyses are employed to characterize the solvation shells of water around the central solute molecules. We have found that water molecules form two solvation shells around the central solute molecule. Hydrogen bonding in the bulk solvent is unaffected by increasing n. The large decrease in solvation enthalpies of these solute molecules for n > 14 enhances solubilisation. The diffusion constants of solute molecules decrease with increasing n. The solvation free energy of C60 in water is positive (52.8 kJ/mol), whereas its value for C60(OH)30 is highly negative (-427.1 kJ/mol). The effects of surface hydroxylation become more dominant once the fullerols become soluble.

  19. "Mixed-solvency approach" - Boon for solubilization of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Maheshwari R

    2010-01-01

    Full Text Available Based on a large number of experiments on solubilization of poorly water-soluble drugs, the author is of the opinion that hydrotropy is another type of cosolvency and all water-soluble substances whether liquids, solids, or gases may act as solubilizers for poorly water-soluble drugs. In the present investigation, a mixed-solvency approach has been utilized for solubility enhancement of poorly water-soluble drug, salicylic acid (as a model drug. Sixteen blends (having total 40% w/v strength of solubilizers containing various solubilizers among the commonly used hydrotropes (urea and sodium citrate, cosolvents (glycerin, propylene glycol, PEG 300 and PEG 400, and water-soluble solids (PEG 4000 and PEG 6000 were made to study the influence on solubility of salicylic acid. Twelve blends were found to increase the solubility of salicylic acid, synergistically. This approach shall prove a boon in pharmaceutical field to develop various formulations of poorly water-soluble drugs by combining various water-soluble excipients in safe concentrations to give a strong solution (say 25% w/v or so to produce a desirable aqueous solubility of poorly water-soluble drugs. In the present investigation, the mixed-solvency approach has been employed to analyze salicylic acid in the bulk drug sample (using six blends precluding the use of organic solvents (a way to green chemistry.

  20. [Study of water-soluble compounds from fungus garden of Odontotermes formosanus].

    Science.gov (United States)

    Xue, Dejun; Zhou, Hui; Zhang, Min; Xie, Kang; Zhang, Yong

    2005-10-01

    To study water-soluble compounds from fungus garden of Odontotermes formosanus. The chemical constituents of fungus garden were analyzed and identified by GC-MS. 28 compounds were separated and 11 chemical constituents were identified. The main constituents in water-solubles from fungus garden of Odontotermes formosanus are palmitic acid, linolei acid and oleic aid.

  1. Biological properties of water-soluble phosphorhydrazone dendrimers

    Directory of Open Access Journals (Sweden)

    Anne-Marie Caminade

    2013-01-01

    Full Text Available Dendrimers are hyperbranched and perfectly defined macromolecules, constituted of branches emanating from a central core in an iterative fashion. Phosphorhydrazone dendrimers constitute a special family of dendrimers, possessing one phosphorus atom at each branching point. The internal structure of these dendrimers is hydrophobic, but hydrophilic terminal groups can induce the solubility of the whole structure in water. Indeed, the properties of these compounds are mainly driven by the type of terminal groups their bear; this is especially true for the biological properties. For instance, positively charged terminal groups are efficient for transfection experiments, as drug carriers, as anti-prion agents, and as inhibitor of the aggregation of Alzheimer's peptides, whereas negatively charged dendrimers have anti-HIV properties and can influence the human immune system, leading to anti-inflammatory properties usable against rheumatoid arthritis. This review will give the most representative examples of the biological properties of water-soluble phosphorhydrazone dendrimers, organized depending on the type of terminal groups they bear.

  2. Water-soluble primary amine compounds in rural continental precipitation

    Science.gov (United States)

    Gorzelska, Krystyna; Galloway, James N.; Watterson, Karen; Keene, William C.

    Procedures for collecting, storing and analysing precipitation samples for organic nitrogen studies were developed. These procedures preserve chemical integrities of the species of interest, allow for up to 3 months storage and quantitative determination of water-soluble primary amine compounds, with the overall error at the 2 nM detection limit of less than 30%. This methodology was applied to study amino compounds in precipitation samples collected over a period of one year in central Virginia. Nitrogen concentrations of 13 amino acids and 3 aliphatic amines were summed to calculate the total amine nitrogen (TAN). The concentration of TAN ranged from below our detection level to 6658 nM, and possibly reflected a seasonal variation in the source strength of the atmospheric amines. Overall, the most commonly occurring amino compounds were methyl amine, ethyl amine, glutamic acid, glycine and serine. On average, the highest overall contribution to the TAN came from arginine, asparagine, glutamine, methyl amine, serine and alanine. However, large qualitative and quantitative variations observed among samples warrant caution in interpretation and application of the averaged values. TAN in Charlottesville precipitation contributed from less than 1 to ca 10% of the ammonium nitrogen level. However, our estimates show that amino compounds may contribute significantly to reduced nitrogen budget in precipitation in remote regions.

  3. Water Soluble Polymers as Proton Exchange Membranes for Fuel Cells

    Directory of Open Access Journals (Sweden)

    Bing-Joe Hwang

    2012-03-01

    Full Text Available The relentless increase in the demand for useable power from energy-hungry economies continues to drive energy-material related research. Fuel cells, as a future potential power source that provide clean-at-the-point-of-use power offer many advantages such as high efficiency, high energy density, quiet operation, and environmental friendliness. Critical to the operation of the fuel cell is the proton exchange membrane (polymer electrolyte membrane responsible for internal proton transport from the anode to the cathode. PEMs have the following requirements: high protonic conductivity, low electronic conductivity, impermeability to fuel gas or liquid, good mechanical toughness in both the dry and hydrated states, and high oxidative and hydrolytic stability in the actual fuel cell environment. Water soluble polymers represent an immensely diverse class of polymers. In this comprehensive review the initial focus is on those members of this group that have attracted publication interest, principally: chitosan, poly (ethylene glycol, poly (vinyl alcohol, poly (vinylpyrrolidone, poly (2-acrylamido-2-methyl-1-propanesulfonic acid and poly (styrene sulfonic acid. The paper then considers in detail the relationship of structure to functionality in the context of polymer blends and polymer based networks together with the effects of membrane crosslinking on IPN and semi IPN architectures. This is followed by a review of pore-filling and other impregnation approaches. Throughout the paper detailed numerical results are given for comparison to today’s state-of-the-art Nafion® based materials.

  4. Monosaccharides as Versatile Units for Water-Soluble Supramolecular Polymers.

    Science.gov (United States)

    Leenders, Christianus M A; Jansen, Gijs; Frissen, Martijn M M; Lafleur, René P M; Voets, Ilja K; Palmans, Anja R A; Meijer, E W

    2016-03-18

    We introduce monosaccharides as versatile water-soluble units to compatibilise supramolecular polymers based on the benzene-1,3,5-tricarboxamide (BTA) moiety with water. A library of monosaccharide-based BTAs is evaluated, varying the length of the alkyl chain (hexyl, octyl, decyl and dodecyl) separating the BTA and saccharide units, as well as the saccharide units (α-glucose, β-glucose, α-mannose and α-galactose). In all cases, the monosaccharides impart excellent water compatibility. The length of the alkyl chain is the determining factor to obtain either long, one-dimensional supramolecular polymers (dodecyl spacer), small aggregates (decyl spacer) or molecularly dissolved (octyl and hexyl) BTAs in water. For the BTAs comprising a dodecyl spacer, our results suggest that a cooperative self-assembly process is operative and that the introduction of different monosaccharides does not significantly change the self- assembly behaviour. Finally, we investigate the potential of post-assembly functionalisation of the formed supramolecular polymers by taking advantage of dynamic covalent bond formation between the monosaccharides and benzoxaboroles. We observe that the supramolecular polymers readily react with a fluorescent benzoxaborole derivative permitting imaging of these dynamic complexes by confocal fluorescence microscopy.

  5. An analytical method for determination of fullerenes and functionalized fullerenes in soils with high performance liquid chromatography and UV detection

    Energy Technology Data Exchange (ETDEWEB)

    Carboni, Andrea, E-mail: A.carboni@uva.nl [University of Amsterdam - IBED, Sciencepark 904, 1098 XH Amsterdam (Netherlands); Emke, Erik [KWR, Watercycle Research Institute, P.O. Box 1072, 3433 PE Nieuwegein (Netherlands); Parsons, John R.; Kalbitz, Karsten [University of Amsterdam - IBED, Sciencepark 904, 1098 XH Amsterdam (Netherlands); Voogt, Pim de [University of Amsterdam - IBED, Sciencepark 904, 1098 XH Amsterdam (Netherlands); KWR, Watercycle Research Institute, P.O. Box 1072, 3433 PE Nieuwegein (Netherlands)

    2014-01-07

    Graphical abstract: -- Highlights: •A total of eight fullerenes can be analyzed in a single run with HPLC-UV. •The method allows the analysis of fullerenes in soil at relatively low concentrations. •The method developed is robust, highly reproducible and relatively efficient. •The method can be applied to the study of the environmental fate and toxicology of fullerenes. -- Abstract: Fullerenes are carbon-based nanomaterials expected to play a major role in emerging nanotechnology and produced at an increasing rate for industrial and household applications. In the last decade a number of novel compounds (i.e. fullerene derivatives) is being introduced into the market and specific analytical methods are needed for analytical purposes as well as environmental and safety issues. In the present work eight fullerenes (C60 and C70) and functionalized fullerenes (C60 and C70 exohedral-derivatives) were selected and a novel liquid chromatographic method was developed for their analysis with UV absorption as a method of detection. The resulting HPLC-UV method is the first one suitable for the analysis of all eight compounds. This method was applied for the analysis of fullerenes added to clayish, sandy and loess top-soils at concentrations of 20, 10 and 5 μg kg{sup −1} and extracted with a combination of sonication and shaking extraction. The analytical method limits of detection (LoD) and limits of quantification (LoQ) were in the range of 6–10 μg L{sup −1} and 15–24 μg L{sup −1} respectively for the analytical solutions. The extraction from soil was highly reproducible with recoveries ranging from 47 ± 5 to 71 ± 4% whereas LoD and LoQ for all soils tested were of 3 μg kg{sup −1} and 10 μg kg{sup −1} respectively. No significant difference in the extraction performance was observed depending of the different soil matrices and between the different concentrations. The developed method can be applied for the study of the fate and toxicity of

  6. The topology of fullerenes

    DEFF Research Database (Denmark)

    Schwerdtfeger, Peter; Wirz, Lukas; Avery, James Emil

    2014-01-01

    graphs and fullerene graphs has grown since they were studied by Goldberg, Coxeter, and others in the early 20th century, and many mathematical properties of fullerenes have found simple and beautiful solutions. Yet many interesting chemical and mathematical problems in the field remain open...

  7. Antibacterial Characteristics and Activity of Water-Soluble Chitosan Derivatives Prepared by the Maillard Reaction

    Directory of Open Access Journals (Sweden)

    Ying-Chien Chung

    2011-10-01

    Full Text Available The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan.

  8. Wave-particle duality of C(60) molecules.

    Science.gov (United States)

    Arndt, M; Nairz, O; Vos-Andreae, J; Keller, C; van der Zouw, G; Zeilinger, A

    1999-10-14

    Quantum superposition lies at the heart of quantum mechanics and gives rise to many of its paradoxes. Superposition of de Broglie matter waves' has been observed for massive particles such as electrons, atoms and dimers, small van der Waals clusters, and neutrons. But matter wave interferometry with larger objects has remained experimentally challenging, despite the development of powerful atom interferometric techniques for experiments in fundamental quantum mechanics, metrology and lithography. Here we report the observation of de Broglie wave interference of C(60) molecules by diffraction at a material absorption grating. This molecule is the most massive and complex object in which wave behaviour has been observed. Of particular interest is the fact that C(60) is almost a classical body, because of its many excited internal degrees of freedom and their possible couplings to the environment. Such couplings are essential for the appearance of decoherence, suggesting that interference experiments with large molecules should facilitate detailed studies of this process.

  9. C60-based clustering scheme for sensor management in STSS

    Institute of Scientific and Technical Information of China (English)

    Yiyu Zhou

    2015-01-01

    Clustering-based sensor-management schemes have been widely used for various wireless sensor networks (WSNs), as they are wel suited to the distributive and col aborative nature of WSN. In this paper, a C60-based clustering algorithm is proposed for the specific planned network of space tracking and surveil ance system (STSS), where al the sensors are partitioned into 12 clus-ters according to the C60 (or footbal surface) architecture, and then a hierarchical sensor-management scheme is wel designed. Final y, the algorithm is applied to a typical STSS constel ation, and the simulation results show that the proposed method has bet-ter target-tracking performance than the nonclustering scheduling method.

  10. Thermodynamics of TMPC/PSd/Fullerene Nanocomposites: SANS Study

    KAUST Repository

    Chua, Yang-Choo

    2010-11-23

    Wereport a small angle neutron scattering study of the thermodynamics of a polymer mixture in the presence of nanoparticles, both in equilibrium and during phase separation. Neutron cloud point measurements and random phase approximation (RPA) analysis demonstrate that 1-2 mass % of C60 fullerenes destabilizes a highly interacting mixture of poly(tetramethyl bisphenol A polycarbonate) and deuterated polystyrene (TMPC/PSd). We unequivocally corroborate these findings with time-resolved temperature jump experiments that, in identical conditions, result in phase separation for the nanocomposite and stability for the neat polymer mixture. At lower C 60 loadings (viz. 0.2-0.5 mass %), stabilization of the mixture is observed. The nonmonotonic variation of the spinodal temperature with fullerene addition suggests a competitive interplay of asymmetric component interactions and nanoparticle dispersion. The stability line shift depends critically on particle dispersion and vanishes upon nanoparticle agglomeration. © 2010 American Chemical Society.

  11. Fullerene and oxidative stress

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2014-07-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to their practical medical using. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance for further promoting of either cytoprotective or cytotoxic effects. One of the main effects of fullerenes on living systems is the reactive oxygen species (ROS formation induction. This lecture provides a modern concept analysis regarding fullerenes effects on ROS formation and modulation of proliferation and apoptosis in normal and tumor cells.

  12. Fullerene and oxidative stress

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2012-01-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to their practical medical using. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance for further promoting of either cytoprotective or cytotoxic effects. One of the main effects of fullerenes on living systems is the reactive oxygen species (ROS formation induction. This lecture provides a modern concept analysis regarding fullerenes effects on ROS formation and modulation of proliferation and apoptosis in normal and tumor cells.

  13. La estructura del fullereno C60 y sus aplicaciones

    OpenAIRE

    VASILIEVNA KHARISSOVA, OXANA; Ortiz Méndez, Ubaldo

    2002-01-01

    Se revisan los datos reportados de una nueva clase de materiales basados en los fullerenos. Se explica la estructura del fullereno C60 y sus compuestos con metales alcalinos, sus propiedades y aplicaciones. Se señala que estos compuestos tienen propiedades de superconducción comparable con la de los tradicionales cupratos. Se indica que esta modificación del carbono puede formar nanotubos que tienen varias aplicaciones prácticas debido a sus propiedades.

  14. Th(IV Adsorption onto Oxidized Multi-Walled Carbon Nanotubes in the Presence of Hydroxylated Fullerene and Carboxylated Fullerene

    Directory of Open Access Journals (Sweden)

    Wangsuo Wu

    2013-09-01

    Full Text Available The adsorption of Th(IV onto the surface of oxidized multi-walled carbon nanotubes (oMWCNTs in the absence and presence of hydroxylated fullerene (C60(OHn and carboxylated fullerene (C60(C(COOH2n has been investigated. C60(OHn, C60(C(COOH2n and oMWCNTs have been chosen as model phases because of their representative in carbon nano-materials family. Adsorption experiments were performed by batch procedure as a function of contact time, pH, ionic strength, and temperature. The results demonstrated that the adsorption of Th(IV was rapidly reached equilibrium and the kinetic process could be described by a pseudo-second-order rate model very well. Th(IV adsorption on oMWCNTs was dependent on pH but independent on ionic strength. Adsorption isotherms were correlated better with the Langmuir model than with the Freundlich model. The thermodynamic parameters calculated from temperature-dependent adsorption isotherms suggested that Th(IV adsorption on oMWCNTs was spontaneous and endothermic. Compared with the adsorption of Th(IV on the same oMWCNTs free of C60(OHn or C60(C(COOH2n, the study of a ternary system showed the inhibition effect of C60(OHn at high concentration on the adsorption of Th(IV in a pH range from neutral to slightly alkaline; whereas the promotion effect of C60(C(COOH2n, even at its low concentration, on Th(IV adsorption was observed in acid medium.

  15. Electronic Structure of Crystalline Buckyballs: fcc-C60

    Science.gov (United States)

    Jalali-Asadabadi, Saeid; Ghasemikhah, E.; Ouahrani, T.; Nourozi, B.; Bayat-Bayatani, M.; Javanbakht, S.; Aliabad, H. A. Rahnamaye; Ahmad, Iftikhar; Nematollahi, J.; Yazdani-Kachoei, M.

    2016-01-01

    The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density functional theory (DFT) approaches including the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), PBE-GGA+DFT-D3(vdW), Engel and Vosko GGA (EV-GGA), GGA plus Hubbard U parameter (GGA+U), hybrids Becke-Perdew-Wang hybrid functional (B3PW91), Becke-Lee-Yang-Parr hybrid functional (B3LYP), the PBE exchange-correlation functional (PBE0), and Tran and Blaha regular and non-regular modified Becke and Johnson (TB-mBJ) potential within a DFT frame work using augmented plane waves plus local orbital method. The comparison of the calculated results with the experimental values shows that the non-regular TB-mBJ method reproduces a correct experimental direct band gap of 2.12 eV at X symmetry for this compound. The effectiveness of this theoretical approach in the reproduction of the experimental band gap is due to the proper treatment of the electrons in the interstitial region of the crystal. Our results show that the C60 clusters are weakly interacting with each other in the fcc crystal. This study also reveals that the five-fold degeneracies of the isolated C60 molecule due to its icosahedral symmetry are completely lifted at an X symmetry point by the crystal field.

  16. Large Enhancement of Optical Nonlinearities of New Organophosphorus Fullerene Derivative

    Institute of Scientific and Technical Information of China (English)

    刘智波; 田建国; 臧维平; 周文远; 张春平; 郑建禺; 周迎春; 徐华

    2003-01-01

    Optical nonlinearities of new organophosphorus fullerene derivative were determined by the Z-scan method with a pulsed Q-switch Nd:YAG laser at 532nm. The experimental results demonstrated that the derivative has much larger excited-states nonlinear absorption and nonlinear refraction than C60. A five-level model was utilized to fit the experimental data, and a good agreement is reached. Some parameters such as excited-state absorption cross and refraction cross were obtained. To our knowledge, the excited-state cross section of new organophosphorus fullerene derivative and its effective ratio to the ground-state cross section are the largest values among the fullerene derivatives reported to date.

  17. Highly Charged Clusters of Fullerenes: Charge Mobility and Appearance Sizes

    Science.gov (United States)

    Manil, B.; Maunoury, L.; Huber, B. A.; Jensen, J.; Schmidt, H. T.; Zettergren, H.; Cederquist, H.; Tomita, S.; Hvelplund, P.

    2003-11-01

    Clusters of fullerenes (C60,C70)n are produced in a gas aggregation source and are multiply ionized in collisions with highly charged Xe20+,30+ ions. Their stabilities and decay processes are analyzed with high-resolution time-of-flight mass spectrometry. Fullerene clusters in charge states up to q=5 have been observed and appearance sizes are found to be as small as napp=5, 10, 21, and 33 for q=2, 3, 4, and 5, respectively. The analysis of the multicoincident fragmentation spectra indicates a high charge mobility. This is in contrast to charge localization effects which have been reported for Arq+n rare gas clusters. Clusters of fullerenes are found to be conducting when multiply charged.

  18. Dissociation of water on Ti-decorated fullerene clusters

    Directory of Open Access Journals (Sweden)

    Yongqiang Xue

    2012-03-01

    Full Text Available Spin-polarized density functional theory calculations have been applied to investigate water dissociation catalyzed by Ti adsorbed on icosahedral C20, C60 and C80 fullerene clusters, in order to elucidate the roles that cluster size and Ti-cluster interaction play in the proposed hydrogen generation reaction. We find that two water molecules can be dissociated consecutively by overcoming moderate energy barriers of a few tenths of eV, accompanied by the generation of a H2 molecule for all three clusters. Depending on the cluster size, the fullerene clusters may participate directly in water splitting or indirectly through stereochemical control of the Ti adsorption sites. Our results suggest that fullerene clusters can serve as a flexible platform for rational design of nanostructured catalysts for hydrogen generation.

  19. Fullerene films and fullerene-dodecylamine adduct monolayers at air-water interfaces studied by neutron and x-ray reflection

    DEFF Research Database (Denmark)

    Wang, J.Y.; Vaknin, D.; Uphaus, R.A.;

    1994-01-01

    Neutron and X-ray reflection measurements and surface pressure isotherms of spread films of the fullerene-dodecylamine adduct C60-[NH2(CH2)11CH3]x all indicate that this material may form monomolecular layers on water surfaces. The reflection data sets (neutron on both H2O and D2O) can be accounted...

  20. Linking Atomistic and Mesoscale Simulations of Water Soluble Polymers

    Science.gov (United States)

    Jones, J. L.

    2003-03-01

    There exist a range of techniques for studying surfactants and polymers in the mesoscale regime. One of the challenges is to link mesoscale theories and simulations to other calculation methods which address different length scales of the system. We introduce some mesoscale methods of calculation for polymers and surfactants and then present a case study of where mesoscale modelling is used for mechanistic understanding, by linking the method to high throughput in-silico screening methods. We look at the adsorption onto silica of ethylene oxide (EO)/ propylene oxide (PO) block copolymers (lutrols) which have been modified by end-grafting of short, cationic dimethylamino ethyl methacrylate (DMAEMA)chains. Given that the silica surface is negatively charged, it is remarkable that in some circumstances, polymers with longercationic chains have a lower adsorption. The effect is attributed to a competition between strong adsorption of the cationic DMAEMA groups driven by electrostatics, and weaker adsorption of the more numerous EO groups. This then raises the question of how we produce the values for the mesoscale parameters in these models and in the second part of the talk we describe a calculation method for doing this for water soluble polymers. The most promising route, but notoriously costly, is based on free energy calculations at the atomistic level. Free energy calculations are computationally intensive in general, but in an aqueous system one is also faced with the additional problem of using complex continuum models and/or accurate interaction potentials for water. Here we show how potential of mean force (PMF)calculations offer a practical alternative which avoids these drawbacks, though one is still faced with extremely long simulations.

  1. Water-soluble ruthenium complexes bearing activity against protozoan parasites.

    Science.gov (United States)

    Sarniguet, Cynthia; Toloza, Jeannette; Cipriani, Micaella; Lapier, Michel; Vieites, Marisol; Toledano-Magaña, Yanis; García-Ramos, Juan Carlos; Ruiz-Azuara, Lena; Moreno, Virtudes; Maya, Juan Diego; Azar, Claudio Olea; Gambino, Dinorah; Otero, Lucía

    2014-06-01

    Parasitic illnesses are major causes of human disease and misery worldwide. Among them, both amebiasis and Chagas disease, caused by the protozoan parasites, Entamoeba histolytica and Trypanosoma cruzi, are responsible for thousands of annual deaths. The lack of safe and effective chemotherapy and/or the appearance of current drug resistance make the development of novel pharmacological tools for their treatment relevant. In this sense, within the framework of the medicinal inorganic chemistry, metal-based drugs appear to be a good alternative to find a pharmacological answer to parasitic diseases. In this work, novel ruthenium complexes [RuCl2(HL)(HPTA)2]Cl2 with HL=bioactive 5-nitrofuryl containing thiosemicarbazones and PTA=1,3,5-triaza-7-phosphaadamantane have been synthesized and fully characterized. PTA was included as co-ligand in order to modulate complexes aqueous solubility. In fact, obtained complexes were water soluble. Their activity against T. cruzi and E. histolytica was evaluated in vitro. [RuCl2(HL4)(HPTA)2]Cl2 complex, with HL4=N-phenyl-5-nitrofuryl-thiosemicarbazone, was the most active compound against both parasites. In particular, it showed an excellent activity against E. histolytica (half maximal inhibitory concentration (IC50)=5.2 μM), even higher than that of the reference drug metronidazole. In addition, this complex turns out to be selective for E. histolytica (selectivity index (SI)>38). The potential mechanism of antiparasitic action of the obtained ruthenium complexes could involve oxidative stress for both parasites. Additionally, complexes could interact with DNA as second potential target by an intercalative-like mode. Obtained results could be considered a contribution in the search for metal compounds that could be active against multiple parasites.

  2. Synthesis and antioxidant activity of [60]fullerene-BHT conjugates.

    Science.gov (United States)

    Enes, Roger F; Tomé, Augusto C; Cavaleiro, José A S; Amorati, Riccardo; Fumo, Maria Grazia; Pedulli, Gian Franco; Valgimigli, Luca

    2006-06-02

    Fullerene derivatives incorporating one or two 3,5-di-tert-butyl-4-hydroxyphenyl groups were synthesized by 1,3-dipolar cycloaddition of azomethine ylides to C(60). The O-H bond dissociation enthalpies (BDEs) of these compounds were estimated by studying, by means of EPR spectroscopy, the equilibration of each of these phenols and 2,6-di-tert-butyl-4-methylphenol (BHT) with the corresponding phenoxyl radicals. The antioxidant activity of the investigated phenols was also determined by measuring the rate constants for their reaction with peroxyl radicals in controlled autoxidation experiments and compared to that recorded under identical experimental settings for [60]fullerene itself and unlinked BHT. The results indicate that linking of the BHT structure to C(60) does not substantially alter the thermochemistry and kinetics of its reaction with peroxyl radicals, but such adducts may behave as interesting bimodal radical scavengers. The inherent rate constant for trapping of peroxyl radicals by C(60) per se (k(inh)=3.1+/-1.1 x 10(2) m(-1) s(-1)) indicates that, contrary to previous reports, [60]fullerene is an extremely weak chain-breaking antioxidant.

  3. Synthesis of a fullerene-based one-dimensional nanopolymer through topochemical transformation of the parent nanowire

    CERN Document Server

    Geng, Junfeng; Reid, David G; Skelton, Paul; Wheatley, Andrew E H; Solov'yov, Andrey V; Johnson, Brian F G

    2009-01-01

    Large-scale practical applications of fullerene (C60) in nanodevices could be significantly facilitated if the commercially-available micrometer-scale raw C60 powder were further processed into a one-dimensional (1D) nanowire-related polymer displaying covalent bonding as molecular interlinks and resembling traditional important conjugated polymers. However, there has been little study thus far in this area despite the abundant literature on fullerene. Here we report the synthesis and characterization of such a C60-based nanowire polymer, (-C60TMB-)n, where TMB=1,2,4-trimethylbenzene, which displays a well-defined crystalline structure, exceptionally large length-to-width ratio and excellent thermal stability. The material is prepared by first growing the corresponding nanowire through a solution phase of C60 followed by a topochemical polymerization reaction in the solid state. Gas chromatography, mass spectrometry and 13C nuclear magnetic resonance evidence is provided for the nature of the covalent bonding...

  4. Nitrogen-doped fullerene as a potential catalyst for hydrogen fuel cells.

    Science.gov (United States)

    Gao, Feng; Zhao, Guang-Lin; Yang, Shizhong; Spivey, James J

    2013-03-06

    We examine the possibility of nitrogen-doped C60 fullerene (N-C60) as a cathode catalyst for hydrogen fuel cells. We use first-principles spin-polarized density functional theory calculations to simulate the electrocatalytic reactions on N-C60. The first-principles results show that an O2 molecule can be adsorbed and partially reduced on the N-C complex sites (Pauling sites) of N-C60 without any activation barrier. Through a direct pathway, the partially reduced O2 can further react with H(+) and additional electrons and complete the water formation reaction (WFR) with no activation energy barrier. In the indirect pathway, reduced O2 reacts with H(+) and additional electrons to form H2O molecules through a transition state (TS) with a small activation barrier (0.22-0.37 eV). From an intermediate state to a TS, H(+) can obtain a kinetic energy of ∼0.95-3.68 eV, due to the Coulomb electric interaction, and easily overcome the activation energy barrier during the WFR. The full catalytic reaction cycles can be completed energetically, and N-C60 fullerene recovers to its original structure for the next catalytic reaction cycle. N-C60 fullerene is a potential cathode catalyst for hydrogen fuel cells.

  5. Exciton-Dissociation and Charge-Recombination Processes in Pentacene/C 60 Solar Cells: Theoretical Insight into the Impact of Interface Geometry

    KAUST Repository

    Yi, Yuanping

    2009-11-04

    The exciton-dissociation and charge-recombination processes in organic solar cells based on pentacene/C60 heterojunctions are investigated by means of quantum-mechanical calculations. The electronic couplings and the rates of exciton dissociation and charge recombination have been evaluated for several geometrical configurations of the pentacene/C60 complex, which are relevant to bilayer and bulk heterojunctions. The results suggest that, irrespective of the actual pentacene-fullerene orientation, both pentacene-based and C60-based excitons are able to dissociate efficiently. Also, in the case of parallel configurations of the molecules at the pentacene/C60 interface, the decay of the lowest charge-transfer state to the ground state is calculated to be very fast; as a result, it can compete with the dissociation process into mobile charge carriers. Since parallel configurations are expected to be found more frequently in bulk heterojunctions than in bilayer heterojunctions, the performance of pentacene/C60 bulk-heterojunction solar cells is likely to be more affected by charge recombination than that of bilayer devices. © 2009 American Chemical Society.

  6. DC Characterisation of C60 Whiskers and Nanowhiskers

    DEFF Research Database (Denmark)

    Larsson, Michael; Kjelstrup-Hansen, Jakob; Lucyszyn, Stepan

    2007-01-01

    C60 whiskers exhibit increasing conductivity with decreasing diameter. At diameters of 1 mm and below, a single-crystal structure predominates, and enhanced electrical characteristics are expected; however, no supporting data exists in the literature. Here, results of four-point probe measurements......, indicating strong potential for use in organic electronic applications of the future. Repeated current cycling in air is observed to promote sample degradation, possibly due to progressive oxidation of the carbon structure. A micromachined four-point probe is also used to try to establish non...

  7. Metal-Insulator Transition in C60-Polymers

    CERN Document Server

    Harigaya, K

    1995-01-01

    Variations in the band structures of C60-polymers are studied, when pi-conjugation conditions are changed. We look at band structures in order to discuss a metal-insulator transition, using a semi-empirical model with the Su-Schrieffer-Heeger type electron-phonon interactions. We find that electronic structures change among direct-gap insulators and the metal, depending on the degree of pi-conjugations. High pressure experiments could observe such pressure-induced metal-insulator transitions.

  8. Terrestrial and extraterrestrial fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Heymann, D.; Jenneskens, L.W.; Jehlicka, J; Koper, C.; Vlietstra, E. [Rice Univ, Houston, TX (United States). Dept. of Earth Science

    2003-07-01

    This paper reviews reports of occurrences of fullerenes in circumstellar media, interstellar media, meteorites, interplanetary dust particles (IDPs), lunar rocks, hard terrestrial rocks from Shunga (Russia), Sudbury (Canada) and Mitov (Czech Republic), coal, terrestrial sediments from the Cretaceous-Tertiary-Boundary and Pennian-Triassic-Boundary, fulgurite, ink sticks, dinosaur eggs, and a tree char. The occurrences are discussed in the context of known and postulated processes of fullerene formation, including the suggestion that some natural fullerenes might have formed from biological (algal) remains.

  9. Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide; Raymond, Kenneth N.

    2008-02-20

    A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-ethane-1,2-diamine [H(2,2)-], N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-propane-1,3-diamine [H(3,2)-] and N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-butane-1,4-diamine [H(4,2)-]. These ligands also incorporate methoxyethylene [MOE] groups on each of the IAM chromophores to increase their water solubility. The aqueous ligand protonation constants and Tb(III) and Eu(III) formation constants were determined from solution thermodynamic studies. The resulting values indicate that at physiological pH, the Eu(III) and Tb(III) complexes of H(2,2)-IAM-MOE and H(4,2)-IAM-MOE are sufficiently stable to prevent dissociation at nanomolar concentrations. The photophysical measurements for the Tb(III) complexes gave overall quantum yield values of 0.56, 0.39, and 0.52 respectively for the complexes with H(2,2)-IAM-MOE, H(3,2)-IAM-MOE and H(4,2)-IAM-MOE, while the corresponding Eu(III) complexes displayed significantly weaker luminescence, with quantum yield values of 0.0014, 0.0015, and 0.0058, respectively. Analysis of the steady state Eu(III) emission spectra provides insight into the solution symmetries of the complexes. The combined solubility, stability and photophysical performance of the Tb(III) complexes in particular make them well suited to serve as the luminescent reporter group in high sensitivity time-resolved fluoroimmunoassays.

  10. Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide; Raymond, Kenneth N.

    2008-02-20

    A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-ethane-1,2-diamine [H(2,2)-], N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-propane-1,3-diamine [H(3,2)-] and N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-butane-1,4-diamine [H(4,2)-]. These ligands also incorporate methoxyethylene [MOE] groups on each of the IAM chromophores to increase their water solubility. The aqueous ligand protonation constants and Tb(III) and Eu(III) formation constants were determined from solution thermodynamic studies. The resulting values indicate that at physiological pH, the Eu(III) and Tb(III) complexes of H(2,2)-IAM-MOE and H(4,2)-IAM-MOE are sufficiently stable to prevent dissociation at nanomolar concentrations. The photophysical measurements for the Tb(III) complexes gave overall quantum yield values of 0.56, 0.39, and 0.52 respectively for the complexes with H(2,2)-IAM-MOE, H(3,2)-IAM-MOE and H(4,2)-IAM-MOE, while the corresponding Eu(III) complexes displayed significantly weaker luminescence, with quantum yield values of 0.0014, 0.0015, and 0.0058, respectively. Analysis of the steady state Eu(III) emission spectra provides insight into the solution symmetries of the complexes. The combined solubility, stability and photophysical performance of the Tb(III) complexes in particular make them well suited to serve as the luminescent reporter group in high sensitivity time-resolved fluoroimmunoassays.

  11. Testing for fullerenes in geologic materials: Oklo carbonaceous substances, Karelian shungites, Sudbury Black Tuff

    Science.gov (United States)

    Mossman, David; Eigendorf, Guenter; Tokaryk, Dennis; Gauthier-Lafaye, François; Guckert, Kristal D.; Melezhik, Victor; Farrow, Catharine E. G.

    2003-03-01

    Fullerenes have been reported from diverse geologic environments since their discovery in shungite from Karelian Russia. Our investigation is prompted by the presence of onionskin-like structures in some carbonaceous substances associated with the fossil nuclear fission reactors of Oklo, Gabon. The same series of extractions and the same instrumental techniques, laser desorption ionization and high-resolution mass spectroscopy (electron-impact mass spectroscopy), were employed to test for fullerenes in samples from three different localities: two sites containing putative fullerenes (Sudbury Basin and Russian Karelia) and one new location (Oklo, Gabon). We confirm the presence of fullerenes (C60 and C70) in the Black Tuff of the Onaping Formation impact breccia in the Sudbury Basin, but we find no evidence of fullerenes in shungite samples from various locations in Russian Karelia. Analysis of carbonaceous substances associated with the natural nuclear fission reactors of Oklo yields no definitive signals for fullerenes. If fullerenes were produced during sustained nuclear fission at Oklo, then they are present below the detection limit (˜100 fmol), or they have destabilized since formation. Contrary to some expectations, geologic occurrences of fullerenes are not commonplace.

  12. Eigenvectors of internal vibrations of C60: Theory and experiment

    Science.gov (United States)

    Heid, R.; Pintschovius, L.; Godard, J. M.

    1997-09-01

    We have studied the eigenvectors of all internal modes of C60 up to 75 meV by inelastic neutron scattering. The experimental data are compared in detail with a state-of-the-art ab initio theory and a phenomenological model of the vibrational spectrum of C60, respectively. We demonstrate that the momentum dependence of mode intensities obtained from measurements on single crystals as well as on powder samples represents a sensitive fingerprint of the eigenvectors which allows (i) unambiguous assignments of silent modes and (ii) discrimination of eigenvectors of modes belonging to the same symmetry class. The latter property can be used for stringent tests of theoretical models. Eigenvectors predicted by the ab initio theory are found to be in very satisfactory agreement with the experimental data, while those obtained from the phenomenological model turn out to be less reliable. We have also performed measurements to study the dispersion of the Hg(1) mode in the low-temperature phase. We found that the data can be largely, although not fully, understood on the basis of a simple van der Waals ansatz for the intermolecular interactions.

  13. Fullerene oxidation and clustering in solution induced by light.

    Science.gov (United States)

    Dattani, Rajeev; Gibson, Kirsty F; Few, Sheridan; Borg, Aaron J; DiMaggio, Peter A; Nelson, Jenny; Kazarian, Sergei G; Cabral, João T

    2015-05-15

    We investigate the environmental stability of fullerene solutions by static and dynamic light scattering, FTIR, NMR and mass spectroscopies, and quantum chemical calculations. We find that visible light exposure of fullerene solutions in toluene, a good solvent, under ambient laboratory conditions results in C60 oxidation to form fullerene epoxides, and subsequently causes fullerene clustering in solution. The clusters grow with time, even in absence of further illumination, and can reach dimensions from ≈100 nm to the μm scale over ≈1 day. Static light scattering suggests that resulting aggregates are fractal, with a characteristic power law (d(f)) that increases from approximately 1.3 to 2.0 during light exposure. The clusters are bound by weak Coulombic interactions and are found to be reversible, disintegrating by mechanical agitation and thermal stress, and reforming over time. Our findings are relevant to the solution processing of composites and organic photovoltaics, whose reproducibility and performance requires control of fullerene solution stability under storage conditions.

  14. Fullerene and apoptosis

    Directory of Open Access Journals (Sweden)

    M. A. Orlova

    2013-01-01

    Full Text Available Fullerene derivatives superfamily attracts a serious attention as antiviral and anticancer agents and drug delivery carriers as well. A large number of such fullerene С60 derivatives obtained to date. However, there is an obvious deficit of information about causes and mechanisms of immediately and long-term consequences of their effects in vivo which is a true obstacle on the way leading to practical medical use of them. First, this concerns their impact on the proliferation, apoptosis and necrosis regulation. Fullerene nanoparticle functionalization type, their sizes and surface nanopathology are of great importance to further promoting of either cytoprotective or cytotoxic effects. This lecture provides modern concept analysis regarding fullerenes effects on apoptosis pathway in normal and tumor cells.

  15. Accurate van der Waals coefficients between fullerenes and fullerene-alkali atoms and clusters: Modified single-frequency approximation

    Science.gov (United States)

    Tao, Jianmin; Mo, Yuxiang; Tian, Guocai; Ruzsinszky, Adrienn

    2016-08-01

    Long-range van der Waals (vdW) interaction is critically important for intermolecular interactions in molecular complexes and solids. However, accurate modeling of vdW coefficients presents a great challenge for nanostructures, in particular for fullerene clusters, which have huge vdW coefficients but also display very strong nonadditivity. In this work, we calculate the coefficients between fullerenes, fullerene and sodium clusters, and fullerene and alkali atoms with the hollow-sphere model within the modified single-frequency approximation (MSFA). In the MSFA, we assume that the electron density is uniform in a molecule and that only valence electrons in the outmost subshell of atoms contribute. The input to the model is the static multipole polarizability, which provides a sharp cutoff for the plasmon contribution outside the effective vdW radius. We find that the model can generate C6 in excellent agreement with expensive wave-function-based ab initio calculations, with a mean absolute relative error of only 3 % , without suffering size-dependent error. We show that the nonadditivities of the coefficients C6 between fullerenes and C60 and sodium clusters Nan revealed by the model agree remarkably well with those based on the accurate reference values. The great flexibility, simplicity, and high accuracy make the model particularly suitable for the study of the nonadditivity of vdW coefficients between nanostructures, advancing the development of better vdW corrections to conventional density functional theory.

  16. Pressure dependence of the solubility of light fullerenes in 1-hexanol from 298.15 K to 363.15 K

    DEFF Research Database (Denmark)

    Semenov, Konstantin N.; Regueira Muñiz, Teresa; Fernández, Josefa

    2015-01-01

    The solubility of light fullerenes (C60 and C70) in 1-hexanol was investigated in the range of pressures of 0.1-100 MPa and in the range of temperatures of 298.15-363.15 K. In all of the studied temperatures, solubility increases monotonously with increasing pressure. At ambient pressure, we have...... (monosolvated fullerene C60 and non-solvated C60). The composition of the solid crystallosolvate was determined by thermogravimetric analysis. The solubility diagram of the binary system C70-1-hexanol in the temperature range of 298.15-328.15 K at 0.1 MPa consists of only one branch corresponding...

  17. Comparative toxicity of water soluble fractions of four oils on the growth of a Microalga

    Digital Repository Service at National Institute of Oceanography (India)

    Phatarpekar, P.V.; Ansari, Z.A.

    Toxic effects of water soluble fractions (WSF) of four different fuel oils on a microalga. Tetraselmis gracilis, were examined and compared. On applying different concentrations of WSF, a decrease in cell population was observed. Depending...

  18. Thermoresponsive synergistic hydrogen bonding switched by several guest units in a water-soluble polymer.

    Science.gov (United States)

    Hao, Zhenhua; Li, Guangxiang; Yang, Ke; Cai, Yuanli

    2013-03-12

    Thermoresponsive synergistic hydrogen bonding (H-bonding) switched by several guest units in a water-soluble polymer is reported. Adjusting the distribution of guest units can effectively change the synergistic H-bonding inside polymer chains, thus widely switch the preorganization and thermoresponsive behavior of a water-soluble polymer. The synergistic H-bonding is also evidenced by converting less polar aldehyde groups into water-soluble oxime groups, which bring about the lowering-down of cloud point and an amplified hysteresis effect. This is a general approach toward the wide tunability of thermosensitivity of a water-soluble polymer simply by adjusting the distribution of several guest H-bonding units.

  19. Explaining Ionic Liquid Water Solubility in Terms of Cation and Anion Hydrophobicity

    Directory of Open Access Journals (Sweden)

    Johannes Ranke

    2009-03-01

    Full Text Available The water solubility of salts is ordinarily dictated by lattice energy and ion solvation. However, in the case of low melting salts also known as ionic liquids, lattice energy is immaterial and differences in hydrophobicity largely account for differences in their water solubility. In this contribution, the activity coefficients of ionic liquids in water are split into cation and anion contributions by regression against cation hydrophobicity parameters that are experimentally determined by reversed phase liquid chromatography. In this way, anion hydrophobicity parameters are derived, as well as an equation to estimate water solubilities for cation-anion combinations for which the water solubility has not been measured. Thus, a new pathway to the quantification of aqueous ion solvation is shown, making use of the relative weakness of interactions between ionic liquid ions as compared to their hydrophobicities.

  20. Synthesis and Characterization of Water-Soluble Carboxymethyl-Cyclodextrin Polymer as Capillary Electrophoresis Chiral Selector

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The water-soluble carboxymethyl-cyclodextrin polymer (CM-CD polymer) was synthesized and used as capillary electrophoresis chiral selector.Verrapamil and thiopentorusodium were well separated using CM-CD polymer as chiral selector.