Fullerene C60 conjugated with L- and D-alanine: integration into lipid bilayer and protection of cell membrane against oxidative stress

Using atomic force microscopy and a fluorescent probe, it was demonstrated that nanoparticles of N-(monohydrofullerenyl)alanine enantiomers effectively embedded into lipid membranes, reduce membrane microviscosity and increase membrane fluidity. Even at a concentration of 1 nM, these C₆₀ fullerene derivatives were found to protect human erythrocytes from free radical-induced hemolysis. The particle sizes of the investigated compounds determined by atomic force microscopy are consistent with small-angle X-ray scattering data indicating the presence of stable aggregate configurations showing a two-fold difference between adjacent maxima in the radius distribution.