Confined systems for environmental and biomedical applications

This PhD thesis explores various confined systems with potential applications in environmental remediation and biomedical technologies. These systems, differing in complexity, were studied to understand the physicochemical processes governing their behavior and effectiveness. The first part of the research focused on the solubilization of dense non-aqueous phase liquids (DNAPLs) using biocompatible ethoxylated surfactants. In particular, Synperonic surfactants demonstrated a significant capacity to enhance DNAPL solubilization by reducing interfacial tension at the DNAPL-water interface and promoting the formation of dispersed systems such as micelles and emulsions. It was observed that, by dissolving into the DNAPL phase, the surfactant locally reduced the surface tension, inducing transverse Marangoni flows, which further facilitated the solubilization process. These findings support the use of Synperonic surfactants as promising agents for contaminated groundwater remediation. The thesis then progresses focusing on the green synthesis of ZIF-8, a porous metal-organic framework composed of zinc ions and imidazolate linkers. ZIF-8 materials are of great interest due to their tunable properties, such as porosity, crystal size, catalytic activity, and gas storage capacity, which depend on both composition and synthesis conditions. Two environmentally friendly synthesis routes were explored. The first involved the use of glycerol carbonate (GC), an industrially relevant green solvent. The transport properties of GC in aqueous media were characterized, and it was subsequently employed for the synthesis of ZIF-8. To improve the e"ciency and control over crystal growth, ZIF-8 precipitation was also studied within an agarose gel matrix under the influence of an electric field. This approach allowed for better control over crystal morphology, contributing to the development of more sustainable and targeted synthesis strategies. The final part of the research investigated the synthesis of hard materials within Giant Unilamellar Vesicles (GUVs). Both ZIF-8 crystals and silver nanoparticles (AgNPs) were successfully synthesized inside these lipid-based compartments. It was found that the presence of the vesicle membrane significantly influenced the nucleation and growth processes, acting as a localized site for precipitation. The ability to generate nanoparticles within soft, biomimetic environments highlights the potential of this method for applications in nanomaterial synthesis, controlled release systems, and biomimetic catalysis.