Nanotubes from a vitamin C-based bolaamphiphile.
A bolaform surfactant, 1,12-diascorbyl dodecanedioate (BOLA12), with ascorbic acid units as the polar headgroups was synthesized for the first time. Once dispersed in water above 0.5% w/w, BOLA12 forms hollow nanotubes as revealed by cryo-TEM experiments. These nanostructures transform into clear micellar solutions on heating. X-ray diffraction and SAXS experiments were performed both on the pure solid and on its aqueous dispersions. The critical aggregation concentration and the phase behavior were determined by conductivity and DSC experiments. The latter technique provided also the amount of strongly bound, solvating water molecules that surround the polar headgroups. BOLA12 shows the same reducing properties of ascorbic acid, as indicated by the antioxidant activity evaluated with the DPPH method. This feature was used for the reduction of Pd(II) ions on the surface of the nanoassemblies, which lead to the formation of large bundles homogeneously coated with palladium as observed in SEM micrographs.
Ambrosi
Moira
M
Department of Chemistry and CSGI, University of Florence, 50019 Sesto Fiorentino (Firenze), Italy.
Fratini
Emiliano
E
Alfredsson
Viveka
V
Ninham
Barry W
BW
Giorgi
Rodorico
R
Lo Nostro
Pierandrea
P
Baglioni
Piero
P
D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes / Q000737:chemistry*; D044367:Phase Transition; D053838:Scattering, Small Angle; D013499:Surface Properties; D013501:Surface-Active Agents / Q000138:chemical synthesis* / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
C521277:1,12-diascorbyl dodecanedioate; D013501:Surface-Active Agents; D014867:Water; D001205:Ascorbic Acid