Synthesizing aqueous fullerene colloidal suspensions by new solvent-exchange methods

Two new solvent exchange methods for synthesizing water-stable colloidal aggregates of C60 are presented. These methods combine key advantages of multiple existing syntheses, including high yield, narrow particle size distribution, potential for control of mean particle size, short synthesis time, and an absence of solvents such as tetrahydrofuran that have historically caused problems in the laboratory syntheses of such aggregates. Further, the synthesis is shown to enrich low-level contamination of samples by C60O. The resulting samples are attractive candidates for use in controlled environmental impact, biological, and toxicity studies.