EPR studies of free radical reactions of C60 embedded in mesoporous MCM-41 materials in aqueous solution

Abstract

The channels of the molecular sieve MCM-41 are employed as nanoreactors to study free radical attacks on C₆₀ in aqueous media. Samples of C₆₀ embedded in the nanochannels of mesoporous materials were prepared by the chemical binding of C₆₀ to the amino-modified surface of MCM-41 solids. The spin trapping/EPR technique was employed to study the reactions of hydroxyl and methyl radicals with the embedded C₆₀ in the nanochannels. The study enables us to examine the chemistry of C₆₀ in aqueous solution, and the efficacy of free radical scavenging by C₆₀ embedded in the nanochannels. The study further reveals the proximity effect of free radical reactions in a nano-restricted environment.