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An approach is proposed for assessment of the thermal properties of aqueous pristine fullerene C60 and C70 dispersions (AFDs) at the level of 10–7–10–5 mol L–1 by photothermal (thermal-lens) spectroscopy for their application in medicine and technology. Along with relevant size-characterization techniquesdifferential scanning calorimetry (DSC) with the Gibbs–Kelvin equation and dynamic light scattering (DLS) techniquesthis approach provides an estimation of the size-dependent thermal properties of disperse solutionsthermal diffusivity, thermal effusivity [thermal inertia], and thermal conductivity. The values for AFDs under the conditions of the attained thermal equilibrium show good precision, and the cluster size estimations agree with the reference methods. The reconstruction of the thermal-lens characteristic time over the course of the blooming of the thermal-lens effect reveals a short increase in the apparent thermal diffusivity. This is accounted for by nonequilibrium heat transfer within fullerene clusters upon initial laser heating, which is supported by the independent estimations from widespread methods like high-resolution transmission electron microscopy, DLS, and DSC. Thermophysical parameters of the disperse phase estimated from transient thermal lensing are as follows: thermal diffusivity, 1.6–2.0 × 10–7 m2 s–1 depending on fullerene concentration and up to 3.5 × 10–7 m2 s–1, more than 2-fold higher than for water; thermal effusivity, 6.7 × 102 J m–2 K–1 s–1/2, three times lower than for water.

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Endohedral metal fullerene are potential nanopharmaceuticals for MRI; thus, it is important to study their effect on reactive oxygen species (ROS) homeostasis. Superoxide anion radical is one of the key ROS. The reactivity of aqueous dispersions of pristine (non-functionalized) fullerenes and Gd@C82 endofullerene have been studied with respect to superoxide in the xanthine/xanthine oxidase chemiluminescence system. It was found that C60 and C70 in aqueous dispersions react with superoxide as scavengers by a similar mechanism; differences in activity are determined by cluster parameters, primarily the concentration of available, acting molecules at the surface. Gd endofullerene is characterized by a significantly (one-and-a-half to two orders of magnitude) higher reactivity with respect to C60 and C70 and is likely to exhibit nanozyme (SOD-mimic) properties, which can be accounted for by the nonuniform distribution of electron density of the fullerene cage due to the presence of the endohedral atom; however, in the cell model, Gd@C82 showed the lowest activity compared to C60 and C70, which can be accounted for by its higher affinity for the lipid phase.