Determination of the equilibrium constant of C₆₀ fullerene binding with drug molecules

Abstract

We report a new analytical method that allows the determination of the magnitude of the equilibrium constant of complexation, K, of small molecules to C fullerene in aqueous solution. The developed method is based on the up-scaled model of C fullerene-ligand complexation and contains the full set of equations needed to fit titration datasets arising from different experimental methods (UV-Vis spectroscopy, H NMR spectroscopy, diffusion ordered NMR spectroscopy, DLS). The up-scaled model takes into consideration the specificity of C fullerene aggregation in aqueous solution and allows the highly dispersed nature of C fullerene cluster distribution to be accounted for. It also takes into consideration the complexity of fullerene-ligand dynamic equilibrium in solution, formed by various types of self- and hetero-complexes. These features make the suggested method superior to standard Langmuir-type analysis, the approach used to date for obtaining quantitative information on ligand binding with different nanoparticles.

Stable and Biocompatible Monodispersion of C60 in Water by Peptides

“…Upon C 60 binding, DOSY experiments showed an increase of 0.54 × 10 –10 m 2 s –1 of the translational diffusion coefficient of the FGGGF peptide (from 3.38 × 10 –10 m 2 s –1 to 3.92 × 10 –10 m 2 s –1 ). Such a change agrees with those reported for small molecule-C 60 complexes. , …”

“…Such a change agrees with those reported for small molecule-C 60 complexes. 69,70 Determination of the Stoichiometry of C 60 @FGGGF Hybrids. Based on the absorption spectra of FGGGF and C 60 in water, a 4:1 stoichiometry is estimated (see SI for details).…”

C60 Fullerene Governs Doxorubicin Effect on Metabolic Profile of Rat Microglial Cells In Vitro

“…In order to detect the complexation between C 60 fullerene and Dox in the aqueous solution, a range of physicochemical methods such as atomic force microscopy, UV–vis, nuclear magnetic resonance, and dynamic lights scattering spectroscopy were applied. , In particular, the small-angle neutron scattering data point out the existence of at least two statistically different entities in aqueous solution, which are the C 60 fullerene aggregates and C 60 –Dox nanocomplexes . Finally, within the proposed thermodynamic model of interaction between C 60 and Dox molecules, we calculated the equilibrium heterocomplexation constant, K L ≈ 60,000 M –1 . Moreover, Dox release from the C 60 –Dox nanocomplex was evaluated by the fluorescent-based technique .…”