Akiko Mizuno

Syntheses and Biological Evaluations of α-d-Mannosyl [60]fullerenols

[60]Fullerenols carrying mono- and bis-alpha-D-mannosyl linkages on the surface were prepared via a [3+2]-cycloaddition reaction between 2-azidoethyl alpha-D-mannoside and C(60) followed by polyhydroxylation with aqueous NaOH. Their biological activity was evaluated in terms of binding affinity to lectins by hemagglutination assay and surface plasmon resonance. [60]Fullerenols without the mannosyl linkage caused aggregation of erythrocytes and binding to a beta-D-galactopyranoside specific lectin (RCA(120)). In contrast, mono- and bis-mannosyl fullerenols were found to decrease the activity for both aggregating erythrocytes and binding to RCA(120), and mono-mannosyl fullerenols turned to binding to alpha-D-mannose specific lectin (Con A).

Syntheses and EELS characterization of water-soluble multi-hydroxyl Gd@C82 fullerenols

Abstract Various water-soluble multi-hydroxyl fullerenes (fullerenols), C60(OH)n, C70(OH)n and C84(OH)n, and a Gd metallo-fullerenols, Gd@C82(OH)n have been synthesized by the Kitazawa method. Elementary chemical analyses indicate that all of these fullerenols have 30–40 hydroxyl groups and 11–15 coordinated water molecules via hydrogen bonds. Electron energy loss spectroscopy (EELS) on Gd@C82 fullerenols shows that the π ∗ peak area in the C K-edge spectra decreases on going from intact Gd@C82 metallofullerene to Gd@C82 fullerenols, indicating an increase in sp3 character of the fullerenols. Furthermore, Gd M4,5-edge EELS spectra show that the encapsulated Gd atom has a trivalent Gd3+ state.