Study of the Aggregation Properties of a Novel Amphiphilic C60-Fullerene Derivative

An amphiphilic C60-derivative, AFE, characterized by the presence of the chiral fragment of L-acetyl carnitine in its hydrophilic appendage has been synthesized. In binary (THF/H2O) and ternary (THF/ MeOH/H2O) solutions, AFE exhibits a strong tendency to self-aggregation, provided that the Hildebrand polarity index, ƒÔ, of the solvent is higher than about 15. A stable aqueous solution of aggregated AFE was obtained. Partition experiments between n-octanol and water show that AFE cannot be spontaneously transferred from water into the organic solvent (and vice versa), although it is effectively ¡§salted-out¡¨ by common electrolytes. Light scattering and reversed-phase liquid chromatography experiments carried out on the aqueous solution of AFE suggest for the aggregates an average diameter of 120 nm.