Inhibition of Drug-Metabolizing Enzymes in Mouse Liver by a Water Soluble Fullerene C60

The microsomal cytochrome P450-dependent monooxygenase system is responsible for the metabolism a variety of xenobiotics including drugs and carcinogens. Fullerenol-1 is a water soluble polyhydroxylated C₆₀ derivative synthesized by a sequence of reactions involving the electrophilic attack of nitronium tetrafluoroborate on fullerenes in the presence of organocarboxylic acids. The present study has evaluated the acute toxicity of fullerenol-1 and determined the effects of the C₆₀ compound on the P450-dependent drug-metabolzing activities. Pretreatments with 0.5 and 1.0g/kg fullerenol-1 decreased P450 and cytochrome b₅ contents, and NADPH-cytochrome P450 reductase, as well as drug metabolizing activities toward test substrates benzo[a]pyrene, 7-ethoxycoumarin, aniline, and erythromycin in liver microsomes. Pretreatments with 0.01 and 0.1 g/kg fullerenol-1 had no effect on these monooxygenases. Immunoblotting anlysis of the microsomal proteins revealed that pretreatments with fullerenol-1 did not alter the protein levels of P450s 1A, 2E and 3A. Additions of fullerenol-1 to mouse liver microsomes suppressed monooxygenases activities toward benzo[a]pyrene, 7-ethoxycoumarin, aniline, and erythromycin with IC₅₀ values of 42, 94, 102 and 349 μM, respectively. These results demonstrate that fullerenol-1 can decrease the activities of microsomal drug-metabolizing enzymes in vivo and in vitro. Proper adjustment of the functionalized fullerene compound may facilitate the biomedical application of the new material.     

In Vitro Effects of Fullerene C60 and Fullerene Black on Immuno-Functions of Macrophages

Bovine alveolar macrophages and HL-60-macrophages were incubated with fullerene C₆₀ and fullerene black particles in native form. No cytotoxic effects were observed. Both types of particles induced the production of Tumor-Necrosis-Factor and interleukin-8 at which fullerene black is more effective. Superoxide anions (O₂) are not released.     

In Vitro Effects of Fullerene C60 and Fullerene Black on Immuno-Functions of Macrophages

Abstract

Bovine alveolar macrophages and HL-60-macrophages were incubated with fullerene C₆₀ and fullerene black particles in native form. No cytotoxic effects were observed. Both types of particles induced the production of Tumor-Necrosis-Factor and interleukin-8 at which fullerene black is more effective. Superoxide anions (O₂) are not released.     

Au电极作用下C60、2C60与4C60富勒烯分子的电子传输特性

采用扩展的Hückel方法与格林函数方法,研究了Au电极作用下,C60富勒烯、2C60和4C60聚合体分子的电子结构与导电性,并对它们的电子结构与电子输运特性进行了对比.研究结果表明,C60、2C60或4C60富勒烯分子与Au电极 "接触"后,其HOMO、LUMO间的能隙减小;C60、2C60或4C60分子与Au电极之间的结合既有共价键的成分,又有离子键的成分,其中,C60、4C60分子与Au电极结合的离子键特征更为明显;三种富勒烯分子的电子输运性能依次具有C60>2C60>4C60分子的顺序.     

Evaluation of Effects of C60 Fullerene and Its Derivatives on Selected Microorganisms

The contribution deals with preparation of C50 fullerene derivatives （oxo derivative, bromo derivative, hydrolyzed bromoderivative, bromo-chloro derivative）, their identification and pilot testing of their biological effects on unicellular organisms. The contribution describes effects of C60 fullerene derivatives, both on prokaryotic organisms （bacteria, cyanobacteria） and eukaryotic organisms （algae） and assesses their potential use as biocides.     

Bromination of [60]Fullerene. II. Crystal and Molecular Structure of [60]Fullerene Bromides, C60Br6, C60Br8, and C60Br24

The crystal and molecular structures of the bromofullerene solvates C₆₀Br₆·0.5C₆H₅Cl·0.5Br₂, C₆₀Br₈·1.5(o-C₆H₄Cl₂), C₆₀Br₈·Br₂, C₆₀Br₈·0.5C₆H₅Br·0.5Br₂, and C₆₀Br₂₄·2Br₂ have been determined by single crystal X-ray diffraction. The molecular species C₆₀Br₆, C₆₀Br₈, and C₆₀Br₂₄ which have idealized C_s, C_2v , and T_h symmetries, respectively, have several different types of C-Br and C-C bonds. A comparison between different solvates of the same bromofullerenes revealed a larger stability of the packing modes for the C₆₀Br₆ and C₆₀Br₂₄ solvates, whereas the C₆₀Br₈ solvates showed different packing motifs dependent on the nature and amount of the solvent molecules.     

Bromination of [60]Fullerene. II. Crystal and Molecular Structure of [60]Fullerene Bromides,C60Br6, C60Br8, and C60Br24

Abstract

The crystal and molecular structures of the bromofullerene solvates C₆₀Br₆·0.5C₆H₅Cl·0.5Br₂, C₆₀Br₈·1.5(o‐C₆H₄Cl₂), C₆₀Br₈·Br₂, C₆₀Br₈·0.5C₆H₅Br·0.5Br₂, and C₆₀Br₂₄·2Br₂ have been determined by single crystal X‐ray diffraction. The molecular species C₆₀Br₆, C₆₀Br₈, and C₆₀Br₂₄ which have idealized C _s , C _2v  , and T _h symmetries, respectively, have several different types of C?Br and C?C bonds. A comparison between different solvates of the same bromofullerenes revealed a larger stability of the packing modes for the C₆₀Br₆ and C₆₀Br₂₄ solvates, whereas the C₆₀Br₈ solvates showed different packing motifs dependent on the nature and amount of the solvent molecules.     

C32C60C180、C60@C180富勒烯分子的压缩力学特性

采用Tersoff-Brenner势与L—J势的分子动力学方法，研究了双石墨层作用下C32、C60、C180以及C60@C180富勒烯分子的压缩力学特性。根据计算结果，讨论了几种富勒烯压缩过程中的变形、能量、压缩栽荷等的变化及其差异。研究表明，由于分子几何构形上的差异，压缩时，C180出现了明显的“塌陷”现象，“塌陷”过程中，能量及外载荷一度下降；几种富勒烯压缩时的能量吸收能力排序为：C32〉C60〉C60@C180〉C180，承载能力的排序为：C60@C180〉C180〉C60〉C32。     

Preparation, Separation and Characterisation of Fullerene - C60 and C70

This paper reports a simple apparatus for the synthesis of fullerenes and an efficient method for the separation of C₆₀ and C₇₀ in large amounts. The positive and negative ion mass spectra of C₆₀ and C₇₀ were measured using electron ionization and in-beam methods. Vibrational Raman spectra showed that the C₆₀ molecule adsorbed on the substrate surface may be distorted and its symmetry may be reduced under the action of the substrate surface.     

Fullerane, the Hydrogenated C60 Fullerene: Properties and Astrochemical Considerations

Hydrogenated C₆₀ fullerene, C₆₀H₃₆ was prepared in different solvents using Zn/HCl as reducing agents. The structure of C₆₀H₃₆ was confirmed both by electronic and FT-IR spectroscopy and the purity of the reaction product was checked by HPLC analysis. It has been confirmed that C₆₀H₃₆ is not stable in air, especially in presence of light which enhances the oxidation. The oxidation of C₆₀H₃₆ was studied by FT-IR spectroscopy and by differential scanning calorimetry (DSC) in air; the formation of hydroxyl groups on the fullerene cage and ketonic groups (involving cage breakdown) have been detected. Furthermore, the action of O₃ on C₆₀H₃₆ was investigated and it has been found that O₃ exerts practically the same effect of air but causing an enhanced cage breakdown. The thermal stability of C₆₀H₃₆ was checked by a thermogravimetric analysis (TGA) coupled with a differential thermal analysis (DTA) under N₂ flow. The vaporization of C₆₀H₃₆ occurs at very high temperature: the DTA trace has shown an endothermic peak at 540°C (at a heating rate of 20°C/min). C₆₀H₃₆ shows an electronic absorption spectrum with a maximum at about 217 nm and it is able to match both in position and in half width the peak at 217.5 nm observed in the spectrum of the interstellar extinction of light which was attributed to hydrogenated, radiation processed and thermally annealed carbon dust. Similarly, the absorption spectrum of C₆₀H₃₆ is able to match several infrared emission bands (called UIBs) detected from certain astrophysical objects like the protoplanetary nebulae (PPNe). It is proposed that hydrogenated fullerenes can be used as model compounds in the laboratory simulation studies of interstellar carbon dust.     

Fullerane,the Hydrogenated C60 Fullerene: Properties and Astrochemical Considerations

Abstract

Hydrogenated C₆₀ fullerene, C₆₀H₃₆ was prepared in different solvents using Zn/HCl as reducing agents. The structure of C₆₀H₃₆ was confirmed both by electronic and FT‐IR spectroscopy and the purity of the reaction product was checked by HPLC analysis. It has been confirmed that C₆₀H₃₆ is not stable in air, especially in presence of light which enhances the oxidation. The oxidation of C₆₀H₃₆ was studied by FT‐IR spectroscopy and by differential scanning calorimetry (DSC) in air; the formation of hydroxyl groups on the fullerene cage and ketonic groups (involving cage breakdown) have been detected. Furthermore, the action of O₃ on C₆₀H₃₆ was investigated and it has been found that O₃ exerts practically the same effect of air but causing an enhanced cage breakdown. The thermal stability of C₆₀H₃₆ was checked by a thermogravimetric analysis (TGA) coupled with a differential thermal analysis (DTA) under N₂ flow. The vaporization of C₆₀H₃₆ occurs at very high temperature: the DTA trace has shown an endothermic peak at 540°C (at a heating rate of 20°C/min). C₆₀H₃₆ shows an electronic absorption spectrum with a maximum at about 217 nm and it is able to match both in position and in half width the peak at 217.5 nm observed in the spectrum of the interstellar extinction of light which was attributed to hydrogenated, radiation processed and thermally annealed carbon dust. Similarly, the absorption spectrum of C₆₀H₃₆ is able to match several infrared emission bands (called UIBs) detected from certain astrophysical objects like the protoplanetary nebulae (PPNe). It is proposed that hydrogenated fullerenes can be used as model compounds in the laboratory simulation studies of interstellar carbon dust.     

Eels and Electron Diffractometry on a Transition from C60 Fullerene to Diamond

A shock induced transition process from C₆₀ fullerene to diamond was examined, exploring changes in electron state and structure by using electron energy-loss spectroscopy and electron diffractometry for the recovered samples from the 16 to 26 GPa compression.     

Radiation-Induced Trichloromethylation of C60 Fullerene in Carbon Tetrachloride

The radiolysis of C₆₀ in CCl₄ has been studied in detail from the organic chemistry point of view. Solutions of C₆₀ in CCl₄ have been treated with γ radiation at 25, 50, 150, and 600 kGy, and the resulting products have been studied by electronic absorption spectroscopy, FT-IR spectroscopy, solid state ¹³C-MAS-NMR and by thermogravimetric analysis. The products have also been separated by liquid chromatographic analysis (HPLC). C₆₀ undergoes a multiple trichloromethylation reaction and on average about 6 trichloromethyl radicals add to the fullerene cage. The trichloromethylation reaction is accompanied by the dimerization and trimerization of C₆₀ fullerene. Also the oligomers appear to be trichloromethyl-substituted.

For reference the C₆₀ solutions in CCl₄ have also been photolyzed with UV light. Similar product as those observed in the radiolysis experiment have been detected. The main difference is that the photolysis products appear both chlorinated and trichloromethylated while the radiolysis product appear almost exclusively trichloromethylated.     

New Developments on the Photochlorination of C60 and C70 Fullerene and Preparation of Fullerene Derivatives: Polyfluorofullerenes and Polyfullerols.

Improved methods for photochlorination of C₆₀ and C₇₀ are described. The photoproducts fit respectively the average formulae C₆₀ Cl₄₀ and C₇₀ Cl₄₇. It is also shown that these photoproducts can be easily fluorinated by means of KF to give fluorofullerenes.

Polyhydroxyfullerene (fullerol) can be easily produced by the action of a methanolic solution of alkali over C₆₀ Cl₄₀.     

New Developments on the Photochlorination of C60 and C70 Fullerene and Preparation of Fullerene Derivatives: Polyfluorofullerenes and Polyfullerols.

Abstract

Improved methods for photochlorination of C₆₀ and C₇₀ are described. The photoproducts fit respectively the average formulae C₆₀ Cl₄₀ and C₇₀ Cl₄₇. It is also shown that these photoproducts can be easily fluorinated by means of KF to give fluorofullerenes.

Polyhydroxyfullerene (fullerol) can be easily produced by the action of a methanolic solution of alkali over C₆₀ Cl₄₀.     

HPLC Diode-Array Analysis of C60 and C70 Polymeric Fullerene Oxides (Fullerene Polymeric Ozonides)

It is shown by HPLC diode-array analysis that the C₆₀ and C₇₀ polymeric fullerene oxides ([C₆₀]-PFOs and [C₇₀]-PFOs) which are polymeric ozonides, are composed by nine different components. The ozonide derivatives of C₆₀ and C₇₀ have been proved to be practically analogous in chemical structure and composition. The most important component of both [C₆₀]-PFOs and [C₇₀]-PFOs accounts for about 3/4 of each sample. The overozonation of [C₆₀]-PFOs in methanol has been studied and shown to not produce any significant changes.     

Effects of γ Radiation on C60 Fullerene in CCI4 Solution

By treating a CCI₄ solution of C₆₀ in a sealed ampoule under argon with γ radiation generated by a ⁶⁰Co source, chlorinated and trichloromethylated C₆₀ oligomers (dimers, trimers) are produced. A total radiation dose of 122 kGy was used.     

The Effects of Radicals on the Formation of Fullerene Ions in Laser Desorption Studies of C60 Adducts

We have studied the fragmentation and aggregation of C₆₀ and its radical adducts R_nC₆₀ by laser-desorption TOF mass spectrometry 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 aggregation products have been discussed. We consider that the electron transfer process between neutral cage-like clusters and the radicals is responsible for the appearance of strong mass peaks of daughter fullerene anions in the case of C₆₀ radical adducts. The effects of the radicals on the fullerene aggregation process have been discussed.     

Search for C60 Fullerene in Char Produced on a Norway Spruce by Lightning

A search was made for C₆₀ fullerene by High Performance Liquid Chromatography in char formed on a Norway Spruce struck by lightning. Firm proof that C₆₀ occurs in the char was not obtained. However, the evidence showed the possible presence of 1 ppb C₆₀.     

Preparation of Two Novel C60 and C70 Fullerene Pyrrolidine Derivatives

Abstract

C₆₀ reacted with paraformaldehyde and DL-valine in dry toluene under nitrogen to give a monoadduct. Under the similar conditions,C₇₀ gave a bisadduct. Both products were characterized by FT-IR,UV-Vis,EI-MS and NMR.The studies of the cyclic voltammetry showed that the abilities of donating electron of the products were increased compared to C₆₀ and C₇₀ respectively.