[Todos] Seminario INQUIMAE/DQIAyQF

[Gabriel Gordillo]

Lunes 22 de marzo 13 hs



Aula Seminarios INQUIMAE-DQIAQF

 Ciudad Universitaria Pab. II Piso 3°

 

"The toxicological Impact of Nanoparticles"



Dr. Roberta Brayner (Associate Professor)
NANOMATERIALS TEAM
Université Paris Diderot (Paris 7)
Interfaces, Traitements, Organisation et Dynamique des Systèmes - ITODYS-CNRS

To produce unique products with novel properties we need to manipulate materials at the nanoscale level. In the word, man-made nanoparticles and materials are being rapidly produced in large quantities and it was shown, in the past ten years that nanomaterials have different toxicity profiles compared with larger particles because of their small size and also their high reactivity. In this moment, the toxicological and environmental effects of direct or indirect exposure to these manufactured nanomaterials are not completely elucidated. The physico-chemistry is essential to understanding the fate and behavior of nanoparticles in the environment, as well as uptake and distribution within organisms, and the interactions of nanoparticles with other pollutants. It has been reported that when the particle size decreases, there is a tendency to increase the toxicity, even if the same material is relatively inert in bulk form (e.g. SiO2, carbon black, TiO2, ZnO). The nanoparticles, due to their nanoscale, shape and consequently huge surface area, may interact more efficiently with biological systems producing important toxicity. In addition, the surface area are directly correlated to many others physico-chemical properties such as chemical reactivity, surface adsorption ability, surface charge, etc. All these factors strongly dominate nanotoxicological behavior in vivo. In addition, the toxicological impact of nanoparticles depends also on the biological target used. In this new multi-disciplinary field, there are many challenges ahead and some controversies, but knowledge transfer from biology, toxicology, colloid chemistry, as well as material and geological sciences, will enable to improve (nano)ecotoxicology studies. The present work is focused on (i) the study of the physico-chemical properties of some nanoparticles (TiO2, ZnO, CdS, Fe, CeO2, carbon nanotubes) prepared without and with protective agents before and after contact with the culture media and also (ii) the study of the ecotoxic impact of these nanoparticles on microorganisms.
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