Preparation of natural zeolitic supports for potential biomedical applications

Considering the biological properties reported for the purified natural clinoptilolite, NZ, we prepared K- and Li-enriched forms aimed at release matrices for biomedical applications. The raw material and the obtained solid samples were characterized by means of atomic absorption spectroscopy, X-ray diffraction, 27Al and 29Si MAS nuclear magnetic resonance, and nitrogen adsorption. The results demonstrated the structural stability of the materials after the different transformations applied. The chemical behavior of the samples in bi-distilled water and hydrochloric acid was studied by pH and conductivity measurements. A preliminary study related with the liberation of K and Li in aqueous medium was carried out by atomic absorption spectroscopy. The studies showed that the release of both ions from the solid samples is favored in HCl solutions, and that lithium is released faster than potassium in both dissolution media.