Amino-acid derivatives of fullerene C60 behave as lipophilic ions penetrating through biomembranes

It was found using potential-sensitive probes that the water-soluble amino-acid derivatives of fullerene C-60, such as C-60-Pro, C-60-epsilon aminocapronic acid, and C-60-Arg, possess a pronounced membranotropic activity. The first two cause concentration-dependent dissipation of the membrane potential (Deltapsi) of the symbiosomes of the nodules of the yellow lupine generated in the presence of ATP and Mg2+ ions. In contrast to the first two derivatives, C-60-Arg, which carries a strong positive charge at the physiological pH, has no effect on the dissipation of Deltapsi in this model. On the contrary, this derivative caused a noticeable dissipation of the K+ diffusion potential ("minus" inside) generated on the membrane of human erythrocytes with the help of the K+ ionophore of valinomycin. The regularities obtained indicate that the derivatives of C-60 are transported across biological membranes as lipophil ions, thus causing depolarization of the membranes. (C) 2002 MAIK "Naukal/Interperiodica".