Free radical scavenging is an important property of fullerenes and their derivatives. In this paper, an aqueous nanoparticle suspension of a bis-methanophosphonate fullerene (n-BMPF) was prepared for the first time. By using a pyrogallol auto-oxidation method combined with spectrophotometry, the activity of n-BMPF against a superoxide anion radical was determined, finding that n-BMPF obtained was considerably stable and suitable for biological assay. In addition, n-BMPF has an excellent efficiency in eliminating superoxide radicals and the effect is dose-dependent. At a concentration of 12 μmol/L, the scavenging efficiency of n-BMPF is 91.96%. Furthermore, n-BMPF has a much higher activity than fullerenol, a water soluble fullerene derivative which has been reported to be able to eliminate free radicals. These data revealed a potential use of BMPF as the novel potent free radical scavengers in biomedical filed.

Key words: aqueous nanoparticle suspension, superoxide anion radical, bis-methanophosphonate [60]fullerene