Molecular Recognition by a Silica-Bound Fullerene Derivative

Abstract

Thermal ring opening of N-[3-(triethoxysilyl)propyl]-2-carbomethoxyaziridine in the presence of C60 produces a fulleropyrrolidine derivative which is then attached covalently to HPLC silica gel. The new chromatographic material is used to investigate binding affinities of potential hosts for the immobilized C60. Exceptionally high size selectivities have been obtained for cyclic oligomeric compounds like calixarenes and cyclodextrins in organic and water-rich media, respectively. A number of rationally designed, helical-shaped peptides bind selectively to the grafted fullerene. The most tightly bound peptide carries two ferrocene moieties at the periphery of a hydrophobic binding cavity complementary in size to C60.