Bis(β-lactosyl)-[60]fullerene as novel class of glycolipids useful for the detection and the decontamination of biological toxins of the Ricinus communis family

Glycosyl-[60]fullerenes were first used as decontaminants against ricin, a lactose recognition proteotoxin in the Ricinus communis family. A fullerene glycoconjugate carrying two lactose units was synthesized by a [3 + 2] cycloaddition reaction between C60 and the azide group in 6-azidohexyl β-lactoside per-O-acetate. A colloidal aqueous solution with brown color was prepared from deprotected bis(lactosyl)-C60 and was found stable for more than 6 months keeping its red color. Upon mixing with an aqueous solution of Ricinus communis agglutinin (RCA120), the colloidal solution soon caused precipitations, while becoming colorless and transparent. In contrast, a solution of concanavalin A (Con A) caused no apparent change, indicating that the precipitation was caused specifically by carbohydrate-protein interactions. This notable phenomenon was quantified by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the results were discussed in terms of detection and decontamination of the deadly biological toxin in the Ricinus communis family.