Abstract
Nanomaterials have received growing attention in the treatment and diagnosis of neurological disorders because the low blood brain barrier permeability hinders the classical pharmacological approach. Metal ion chelators combined with nanoparticles prove effective in the treatment of neurodegeneration and are under extensive studies. Most chelating agents and metallodrugs compete with endogenous molecules for metal coordination, and do not reach the active site. Determining the competition between metallodrugs and endogenous molecules requires knowing the stability constants of formed metal complexes. In this study, for the first time, potentiometric titrations are used to determine metal complex formation constants, and to quantify ligand content in functionalized materials. This new potentiometric approach allows physico–chemical characterization of mesoporous functionalized materials and their metal adsorption capacity in water solution. The potentiometric results are compared with isotherm models obtained by spectroscopic measurements and yield rewarding data fitting. The potentiometric method described here can be extended to different types of nanostructured materials carrying surface ionizable groups.
Scientific interest of nanomaterials as metal chelators in the treatment and diagnosis of neurological disorders is growing and needs proper techniques for the investigation of metal–ligand interactions. Potentiometry determines ligand content, metal complex stability constants, and competition between metallodrugs and endogenous molecules. Combined electron paramagnetic resonance, nuclear magnetic resonance, and potentiometry experiments improve metal adsorption studies on functionalized nanomaterials.