The observed orientation of C3 upon its absorption to the membrane surface appears to play a crucial role in efficient scavenging of ROS and radical protection: It resides not inside the membrane but near the lipid tail region, preventing chain peroxidation of the lipids. The isomeric form of C3–D3– does not have [35] such high cytoprotective properties since its three malonic acid residues cover the fullerene surface symmetrically (Figure 1B) and D3 only adsorbs efficiently to the region of the lipid headgroups where the distance from the COM of the membrane equals 2 nm and retains its solvent shell (see Figure 5C).