Doped ZnO nanoparticles in biomedicine: their role as stimuli-responsive anticancer agents

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Artificial and Naturally Derived Phospholipidic Bilayers as Smart Coatings of Solid-State Nanoparticles: Current Works and Perspectives in Cancer Therapy

Recent advances in nanomedicine toward cancer treatment have considered exploiting liposomes and extracellular vesicles as effective cargos to deliver therapeutic agents to tumor cells. Meanwhile, solid-state nanoparticles are continuing to attract interest for their great medical potential thanks to their countless properties and possible applications. However, possible drawbacks arising from the use of nanoparticles in nanomedicine, such as the nonspecific uptake of these materials in healthy organs, their aggregation in biological environments and their possible immunogenicity, must be taken into account. Considering these limitations and the intrinsic capability of phospholipidic bilayers to act as a biocompatible shield, their exploitation for effectively encasing solid-state nanoparticles seems a promising strategy to broaden the frontiers of cancer nanomedicine, also providing the possibility to engineer the lipid bilayers to further enhance the therapeutic potential of such nanotools. This work aims to give a comprehensive overview of the latest developments in the use of artificial liposomes and naturally derived extracellular vesicles for the coating of solid-state nanoparticles for cancer treatment, starting from in vitro works until the up-to-date advances and current limitations of these nanopharmaceutics in clinical applications, passing through in vivo and 3D cultures studies

Iron-Doped ZnO Nanoparticles as Multifunctional Nanoplatforms for Theranostics

Zinc oxide nanoparticles (ZnO NPs) are currently among the most promising nanomaterials for theranostics. However, they suffer from some drawbacks that could prevent their application in nanomedicine as theranostic agents. The doping of ZnO NPs can be effectively exploited to enhance the already-existing ZnO properties and introduce completely new functionalities in the doped material. Herein, we propose a novel synthetic approach for iron-doped ZnO (Fe:ZnO) NPs as a multifunctional theranostic nanoplatform aimed at cancer cell treatment. Pure ZnO and Fe:ZnO NPs, with two different levels of iron doping, were synthesized by a rapid wet-chemical method and analyzed in terms of morphology, crystal structure and chemical composition. Interestingly, Fe:ZnO NPs featured bioimaging potentialities thanks to superior optical properties and novel magnetic responsiveness. Moreover, iron doping provides a way to enhance the electromechanical behavior of the NPs, which are then expected to show enhanced therapeutic functionalities. Finally, the intrinsic therapeutic potentialities of the NPs were tested in terms of cytotoxicity and cellular uptake with both healthy B lymphocytes and cancerous Burkitt’s lymphoma cells. Furthermore, their biocompatibility was tested with a pancreatic ductal adenocarcinoma cell line (BxPC-3), where the novel properties of the proposed iron-doped ZnO NPs can be potentially exploited for theranostics

Modèles stochastiques et fluides au niveau flot de réseaux TCP/IP

Plus de trente ans après sa spécification, le Transmission Control Protocol (TCP) motive encore de la recherche autour de lui. Cette thèse porte sur la modélisation analytique du protocole TCP dans les réseaux IP. Au coeur de cette représentation est, en fait, la notion d une connexion TCP comme un flux de données continu dans l espace et dans le temps. L abstraction du niveau paquet au niveau flux est à la base de l application de modèles fluides à la représentation dynamique du protocole TCP et c est le substrat commun de la thèse. Elle implique une caractérisation de la dynamique du système en termes de equations aux dérivées partielles. La contribution de la thèse est double et elle se traduit par l organisation de la thèse en deux parties principales. La première partie de la thèse étudie les modèles à flux unique et se focalise sur l interaction microscopique des flux TCP en série. La deuxième partie de la thèse adopte une perspective macroscopique en décrivant la dynamique d un grand nombre de flux TCP. Si la première partie de la thèse se concentre sur l abstraction de paquet a flux lors de l examen de quelques connexions TCP, ici nous avons egalement fait abstraction du flux TCP particulier dans la classe de flux TCP qui partagent le même chemin a travers le réseau.More than thirty years after its specification, the Transmission Control Protocol (TCP) still motivates research around it. This dissertation focuses on the analytical modelling of TCP/IP networks at flow level. At the heart of this representation, indeed, is the notion of a TCP connection as a stream of data, continuous in space and in time, and not as a discrete sequence of packets, as in reality. The packet-to-flow abstraction is at the basis of the application of fluid models to the representation of TCP dynamics and it is the common susbstrate of the thesis. The contribution of the thesis is twofold and it is reflected by the organization of the thesis in two main parts. The first part of the thesis focuses of the model of a single flow and studies the microscopic interaction of TCP flows in series. The second part of the thesis adopts a macroscopic perspective in describing the dynamics of a large population of TCP flows. If the first part of the thesis lies on the abstraction from packets to flow dynamics when looking at a few TCP connections, here we also abstract the single TCP flow into the class of TCP flows sharing the same path through the network..PARIS-Télécom ParisTech (751132302) / SudocSudocFranceItalyFRI

Rapid prototyping of multilayer thiolene microfluidic chips by photopolymerization and transfer lamination

A new fabrication process is described allowing rapid prototyping of multilayer microfluidic chips using commercial thiolene optical adhesives. Thiolene monomer liquid is photopolymerized across transparency masks to obtain partially cured patterns supported on thin polyethylene sheets. The patterns are easily laminated and transferred to a substrate due to the elastomeric nature and adhesiveness of partially cured thiolene. The process characteristics are evaluated by realizing several test structures and fluidic chips. As an example of application, the operation of a microfluidic bead array sensor for pH measurements is then described in some detail

Insight into Sonoluminescence Augmented by ZnO-Functionalized Nanoparticles

Recent advances in optical imaging techniques rely on the use of nanosized contrast agents for in vitro and in vivo applications. We report on an imaging method based on the inertial cavitation of ultrasound-irradiated water solutions that lead to sonoluminescence (SL), here, newly proposed in combination with semiconductor nanoparticles, in particular, aminopropyl-functionalized zinc oxide nanocrystals. The obtained measurements confirm the ability of such nanocrystals to increase the sonoluminescence emission, together with the ability to modify the SL spectrum when compared to the pure water behavior. In particular, it is shown that the UV component of SL is absorbed by the semiconductor behavior that is also confirmed in different biologically relevant media. Finally, optical images of nanocrystal-assisted SL are acquired for the first time, in particular, in biological buffers, revealing that at low ultrasound intensities, SL is measurable only when the nanocrystals are present in solution. All of these results witness the role of amine-functionalized zinc oxide nanocrystals for sonoluminescence emission, which makes them very good candidates as efficient nanocontrast agents for SL imaging for biological and biomedical applications