Amphiphilic poly(phenylquinoline)-block-polystyrene rod-coil diblock copolymers were observed to self-organize into robust, micrometer-scale, spherical, vesicular, cylindrical, and lamellar aggregates from solution. These diverse aggregate morphologies were seen at each composition, but their size scale decreased with a decreasing fraction of the rigid-rod block. Compared to coil-coil block copolymer micelles, the present aggregates are larger by about two orders of magnitude and have aggregation numbers of over 10(8). The spherical and cylindrical aggregates have large hollow cavities. Only spherical aggregates with aggregation numbers in excess of 10(9) were formed in the presence of fullerenes (C60, C70) in solution, resulting in the solubilization and encapsulation of over 10(10) fullerene molecules per aggregate.

https://science.sciencemag.org/content/sci/279/5358/1903.full.pdf

Self-Assembled Aggregates of Rod-Coil Block Copolymers and Their Solubilization and Encapsulation of Fullerenes

Fullerene derivatives: an attractive tool for biological applications

To characterize fullerenes (C60 and C70) as photosensitizers in biological systems, the generation of active oxygen species, through energy transfer (singlet oxygen 1O2) and electron transfer (reduced active oxygen radicals such as superoxide anion radical O2-• and hydroxyl radical •OH), was studied by a combination of methods, including biochemical (DNA-cleavage assay in the presence of various scavengers of active oxygen species), physicochemical (EPR radical trapping and near-infrared spectrometry), and chemical methods (nitro blue tetrazolium (NBT) method). Whereas 1O2 was generated effectively by photoexcited C60 in nonpolar solvents such as benzene and benzonitrile, we found that O2-• and •OH were produced instead of 1O2 in polar solvents such as water, especially in the presence of a physiological concentration of reductants including NADH. The above results, together with those of a DNA cleavage assay in the presence of various scavengers of specific active oxygen species, indicate that the active...

Active Oxygen Species Generated from Photoexcited Fullerene (C60) as Potential Medicines: O2-• versus 1O2

Chem. Rev. 2000, 100, 1075−1120 Discrete Fulleride Anions and Fullerenium Cations Christopher A. Reed* and Robert D. Bolskar Department of Chemistry, University of CaliforniasRiverside, Riverside, California 92521-0403 Received June 22, 1999 Contents I. Introduction, Scope, and Nomenclature II. Electrochemistry A. Reductive Voltammetry B. Oxidative Voltammetry III. Synthesis A. Chemical Reduction of Fullerenes to Fullerides i. Metals as Reducing Agents ii. Coordination and Organometallic Compounds as Reducing Agents iii. Organic/Other Reducing Agents B. Electrosynthesis of Fullerides C. Chemical Oxidation of Fullerenes to Fullerenium Cations IV. Electronic (NIR) Spectroscopy A. Introduction B. C 60 n- Fullerides C. C 70 and Higher Fullerenes D. Fullerenium Cations E. Diffuse Interstellar Bands V. Vibrational Spectroscopy A. Infrared Spectroscopy B. Raman Spectroscopy VI. X-ray Crystallography A. Introduction B. [PPN] 2 [C 60 ] and Related C 602- Structures C. C 60 - Structures D. C 603- Structures E. Comparison of Discrete and Extended Structures VII. Magnetic Susceptibility and Spin States VIII. NMR Spectroscopy A. Introduction B. 13 C NMR Data in Solution C. Interpretation of Solution NMR Data D. 13 C NMR Data in the Solid State E. Knight Shift in A 3 C 60 F. 3 He NMR of Endohedral Fullerides G. 13 C NMR of Derivatized Fullerenes H. 13 C NMR of Fullerenium Cations IX. EPR Spectroscopy A. Introduction B. Features of the C 60 - Spectrum i. The Low g Value ii. Temperature Dependence of the Line Width (∆H pp ) X. XI. XII. XIII. iii. Anisotropy iv. Problem of the Sharp Signals v. Origins of Sharp Signals vi. The C 120 O Impurity Postulate vii. The Dimer Postulate C. Features of the C 602- EPR Spectrum D. Features of the C 603- EPR Spectrum E. Features of C 604- and C 605- EPR Spectra F. EPR Spectra of Higher Fullerides G. EPR Spectra of Fullerenium Cations Chemical Reactivity A. Introduction B. Fulleride Basicity C. Fulleride Nucleophilicity/Electron Transfer D. Fullerides as Intermediates E. Fullerides as Catalysts F. Fullerides as Ligands G. Fullerenium Cations Conclusions and Future Directions Acknowledgments References I. Introduction, Scope, and Nomenclature The electron-accepting ability of C 60 , the archetypal fullerene, is its most characteristic chemical property. It is a natural consequence of electronic structure and was anticipated in early molecular orbital calcula- tions 1 which place a low-lying unoccupied t 1u level about 2 eV above the h u HOMO: 2-4 Early in the gas-phase investigations of fullerenes, the electron affinity of C 60 was measured and found to be high (2.69 eV). 5-7 When the macroscopic era of C 60 chemistry began in 1990, this property was soon found to translate into the solution phase. 8 In a rather remarkable cyclic voltammogram (see Figure 1), the reversible stepwise addition of up to six electrons was soon demonstrated electrochemically. 9,10 10.1021/cr980017o CCC: $35.00 © 2000 American Chemical Society Published on Web 02/16/2000

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Discrete fulleride anions and fullerenium cations.

Characterization and remediation of soils contaminated with uranium.

Solubility of C60 in organic solvents

A Knudsen cell mass spectrometric study of pure C{sub 60} was carried out in the temperature range 600-800 K to obtain the vapor pressure and enthalpy of sublimation. The measured appearance potential for C{sub 60}{sup +} (8.1 {plus_minus}0.5 V) is in good agreement with the recommended value (7.6 {plus_minus} 0.2 V) for the ionization potential of C{sub 60}. The enthalpy of sublimation was found to be 181.4 {plus_minus} 2.3 kJ/mol at 700 K by the second law method. The vapor pressure of C{sub 60} is given as a function of temperature by the equation log (p/Pa)=-9777 {plus_minus} 138/T (K) + 11.582 {plus_minus} 0.126. 13 refs., 2 figs., 3 tabs.

Vaporization studies on buckminsterfullerene

Solubility of fullerene C60 in 75 organic solvents was examined to develop quantitative structure-solubility relationships. Topological indices and polarizability parameter computed from refractive index were used to form the regression models. The models suggested for individual data sets such as alkanes, aklyl halides, alcohols, cycloalkanes, alkylbenzenes, and aryl halides have good predictive ability and are better than the models for the combined groups. Inclusion of an indicator parameter which is a combination of atom contributions and contributions of substituents' position in benzenes improved the predictive ability significantly.

QSPR Modeling for Solubility of Fullerene (C60) in Organic Solvents

In this paper, a new Th4+ ion-selective chromogenic sensor (L) was developed by reacting 1,10-phenanthroline-2,9-dicarbohydrazide with 2-hydroxy naphthaldehyde. The sensing ability of L toward Th4+ was investigated in solution and paper strips loaded with L using spectrophotometric and colorimetric methods. The selective interaction of L was examined with various f-metal ions and other selected metal ions from s-block and d-block elements. Results show that by the colorimetric method in solution-phase dimethyl sulfoxide/H2O (7:3, v/v) and paper strip methods, the naked-eye detectable color change of L occurred from colorless solution to yellow-orange and pale yellow colour upon interacting with Th4+ and Al3+, respectively, whereas other metal ions did not interfere. The ligand L exhibits two absorbance bands at 320 and 375 nm because of ligand-to-ligand charge transfer. Upon interaction with Th4+, L undergoes red shift of both absorption bands and the formation of a new UV-vis band at 335 and 440 nm. The UV-visible spectral studies indicate the formation of a 1:1 host-guest complex between L and Th4+ with an association constant of 4.7 × 103 M-1. The limit of quantification and limit of detection of L for the analysis of Th4+ are found to be 167 and 50 nM, respectively. The visually detectable color change of L has been well integrated with a smartphone RGB color value to make it an analytical signal for real-time analysis of Th4+ with the detection limit down to 116 nM. Besides, L was applied for the analysis of Th4+ content present in various real water samples, monazite, and lantern mantle samples by spectrophotometry and RGB color values. The binding mode of L with Th4+ is investigated by 1H NMR, electrospray ionization-mass, and theoretical studies.

Development of the Smartphone-Assisted Colorimetric Detection of Thorium by Using New Schiff’s Base and Its Applications to Real Time Samples

The solubility of C70 in various organic solvents has been measured at 303 K for the first time. The solubilities vary from 2 μg/ml in pentane to 36 mg/m1 in o-dichlorobenzene. The solubility is correlated with solvent properties such as Hildebrand solubility parameter and polarisability. The solubility parameter shows good correlation with the solubility for most of the organic solvents studied, with the exception of carbon disulphide and o-dichlorobenzene. The polarisability parameter also explains the wide range of solubility in various organic solvents. However, both the solvent parameters do not satisfactorily explain the trend in the observed solubility over the entire range of solvents.

N. Sivaraman

Papers

Solubility of C60 in organic solvents

Vaporization studies on buckminsterfullerene

QSPR Modeling for Solubility of Fullerene (C60) in Organic Solvents

Development of the Smartphone-Assisted Colorimetric Detection of Thorium by Using New Schiff’s Base and Its Applications to Real Time Samples

Solubility of C70 in Organic Solvents