(377j) Chitosan Functionalized with Histidine to Increase Metal Ions Adsorption

Chelating nanoparticles able to cross the blood-brain barrier (BBB) can be an effective pharmacological treatment to Alzheimer’s disease (AD). Chitosan microparticles (CM) associated with histidine (composed by imidazole functionalities, to mimetize the Aβ peptide) were used to chelate copper, zinc and iron. CM (prepared by spray-drying) and CM-histidine were characterized by SEM, XRD and potenciometric titration. The equilibrium data of metallic ions adsorbed onto chitosan-histidine systems were described by Langmuir and Sips models. The estimation of the mass transfer parameters was carried out using the Pore-Surface Diffusion Model. Histidine presented highest adsorption capacity for copper ions, which increased the adsoption capacity for chitosan-histidine compared to chitosan system. This is a very interesting finding for metal ions separation, with chelating potential to treat heavy metal poisoning.