Studies on the interactions between components of natural waters (alkali metal ions or alkaline earth metals) with low molecular weight ligands of environmental interest (carbonates, phosphates) and biological interest (amino acids, carboxylates, nucleotides). Different modeling approaches have been used to define interaction parameters [SIT (Specific ion Interaction Theory), Pitzer, and Ionic Association model]. Investigations on the acid-base properties of high molecular weight synthetic ligands (polyacrylates and polymethacrylates) and natural ligands (alginate, chitosan, pectin, humic and fulvic acids) and on the formation of complex species with metal ions and organometallics in different ionic media and at different ionic strengths, aimed at defining the dependence of protonation constants and complex formation on ionic strength, and their capacity as sequestering agents for ions of toxic metals. Studies on the binding capacity of organic and inorganic soils, aimed at defining the bioavailability of essential and toxic metal ions. Development of chemical speciation models capable of predicting the chemical behavior of different classes of ligands in natural fluids, with particular reference to marine waters. Formulation and characterization of composites (halloysite nanotubes) and biopolymers, to study the selective adsorption of organic and inorganic pollutants. Analysis of different contaminants and their ecotoxicological impact in natural environments, aimed at environmental control and monitoring. Characterization, biodegradation, and environmental risks associated with bioplastics. Theoretical and practical studies on the behavior of zirconium and hafnium in natural waters. Separative analytical methods for the characterization of food and environmental matrices