Synthesis and evaluation of anticancer activity in cells of novel stoichiometric pegylated fullerene-doxorubicin conjugates.

Purpose: To synthesize pegylated stoichiometrically and structurally well-defined conjugates of fullerene (C60) with doxorubicin (DOX) and investigate their antiproliferative effect against cancer cell lines.

Methods: Stoichiometric (1:1 and 1:2) pegylated conjugates of C60 with DOX were synthesized using the Prato reaction to create fulleropyrrolidines equipped with a carboxyl function for anchoring a polyethylene glycol (PEG) moiety and either a hydroxyl group for attaching one molecule of DOX or a terminal alkyne group for attaching two molecules of DOX through a click reaction. In both conjugates, the DOX moieties are held through a urethane-type bond.