Physicochemical characterization of the evolution of metal nanoparticles in biological and environmental media: from synthesis to interaction with living organisms
- Autores: Francesco Barbero
- Directores de la Tesis: Victor Franco Puntes (dir. tes.)
- Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2019
- Idioma: español
- Tribunal Calificador de la Tesis: Silvia Pujals Riatós (presid.), Julia Lorenzo Rivera (secret.), Inhar Imaz (voc.)
- Programa de doctorado: Programa de Doctorado en Ciencia de Materiales por la Universidad Autónoma de Barcelona
- Materias:
- Enlaces
- Tesis en acceso abierto en: TESEO
- Resumen
The increasing production of engineered Nanoparticles (NPs) will inevitably lead to an increase of human and environmental exposition to these materials. Consequently reasonable concerns have arisen regarding their potential safety risks, giving rise to the nanotoxicology/nanosafety discipline.
Because of the high reactivity, NPs exposed to different biological and environmental scenarios, tend to reach a more stable thermodynamic state via aggregation, interaction with the molecules present in the environment, adsorption to macro-organic matter, chemical transformations and dissolution. All these transformations can generate a new identity of the nano-objects or produce new chemical entities, thereby changing their behaviour and consequently their potential associated risk. Thus, the same NPs can have a totally different fate and consequently a totally different impact on living organisms and the environment depending on the microenvironment (e.g., the exposure medium) in which they are. Furthermore, the pristine features of nano-material highly influence their biological and environmental fate. From this perspective, it becomes fundamental to understand the characteristics of the final object that will encounter living organisms and analyze its properties, in order to correlate the pristine and final NP features with the potential effects on living organisms.
In this context, the focus of this thesis has been on the physicochemical transformation of model NPs exposed to biological and environmental media. For these studies, Au and Ag NPs were chosen as they are widely used NP models and because of their numerous applications. Firstly, the study focused on the influence of the cell culture media composition on the protein corona (PC) formation process, final composition and NPs aggregation state and the consequent effects on NP cell uptake. A physicochemical characterization of the nature of the CTAB - Au NP bilayer was also carried out to study the impact of this widely used NP surface coating on the particle's exposition to biological fluids, on the formation of the protein corona and on the design and interpretation of NP toxicity tests. Finally, the NP evolution in natural fresh water was explored by carrying out a study of the interaction nature of NPs and natural organic matter and the deriving NP features.
