A therapy of cancer cells: Two-photon-triggered camptothecin delivery (see picture) with nanoimpellers was studied in MCF-7 breast cancer cells. A fluorophore with a high two-photon absorption cross-section was first incorporated in the nanoimpellers. Fluorescence resonance energy transfer (FRET) from the fluorophore to the azobenzene moiety was demonstrated.

Magnetic mesoporous silica nanoparticles (M-MSNs) represent promising targeting tools for theranostics. Engineering the interaction of nanoparticles (NPs) with biological systems requires an understanding of protein corona formation around the nanoparticles as this drives the biological fate of nanocarriers. We investigated the behavior of proteins in contact with M-MSNs by high-throughput comparative proteomics, using human and bovine sera as biological fluids, in order to assess the adsorption dynamics of proteins in these media. Using system biology tools, and especially protein-protein interaction databases, we demonstrated how the protein network builds up within the corona over the course of the experiment. Based on these results, we introduce and discuss the role of the "corona interactome" as an important factor influencing protein corona evolution. The concept of the "corona interactome" is an original methodology which could be generalized to all NP candidates. Based on this, pre-coating nanocarriers with specific proteins presenting minimal interactions with opsonins might provide them with properties such as stealth.

The uptake and release capacities of mesoporous silica particles are measured on nanovalve-gated stimulated release systems, using a water soluble biological stain, Hoechst 33342, as the cargo model. Five different types of mesoporous silica nanoparticles: 2D-hexagonal MCM-41, swollen pore MCM-41, rod-like MCM-41, hollow mesoporous nanoparticles and radial mesoporous nanoparticles are studied and compared. Solid silica nanoparticles are used as the control. Because of the presence of the nanovalves, the loaded and capped particles can be washed thoroughly without losing the content of the mesopores. The quantity of Hoechst 33342 molecules trapped within the nanoparticles and released upon opening the nanovalves are systematically studied for the first time. The loading conditions are optimized by varying the Hoechst concentration in the loading solutions. Surprisingly, increasing the Hoechst concentration in the loading solution does not always result in a larger amount of Hoechst being trapped and released. Among the five types of mesoporous silica nanoparticles, the radial mesoporous nanoparticles and the swollen pore MCM-41 particles show the highest and lowest release capacity, respectively. The uptake capacities is correlated with the specific surface area of the materials rather than their internal volume. The uptake and release behaviors are also affected by charge and spatial factors.

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Careful analysis of any new nanomedicine device or disposal should be undertaken to comprehensively characterize the new product before application, so that any unintended side effect is minimized. Because of the increasing number of nanotechnology-based drugs, we can anticipate that regulatory authorities might adapt the approval process for nanomedicine products due to safety concerns, e.g., request a more rigorous testing of the potential toxicity of nanoparticles (NPs). Currently, the use of mesoporous silica nanoparticles (MSN) as drug delivery systems is challenged by a lack of data on the toxicological profile of coated or non-coated MSN. In this context, we have carried out an extensive study documenting the influence of different functionalized MSN on the cellular internalization and in vivo behaviour. In this article, a synthesis of these works is reviewed and the perspectives are drawn. The use of magnetic MSN (Fe3O4@MSN) allows an efficient separation of coated NPs from cell cultures with a simple magnet, leading to results regarding corona formation without experimental bias. Our interest is focused on the mechanism of interaction with model membranes, the adsorption of proteins in biological fluids, the quantification of uptake, and the effect of such NPs on the transcriptomic profile of hepatic cells that are known to be readily concerned by NPs’ uptake in vivo, especially in the case of an intravenous injection.

Supported copper oxide nanoparticles are a potential candidate for replacing the rare and expensive precious metals within the automotive three-way catalyst. However, a well-designed dispersion method is necessary to allow a stable high loading of active material, compensating its lower intrinsic activity and stability. In this work, a CuO-loaded SBA-15 catalyst has been manufactured by two methods. The ammonia-driven deposition precipitation (ADP) and the molecular designed dispersion (MDD) methods are both considered as efficient deposition methods to provide well-dispersed copper oxide-based catalysts. Their morphology, copper dispersion and the chemical state of copper were characterized and compared. Due to the differences in the synthesis approach, a difference in the obtained copper oxide phases has been observed, leading to a distinct behavior in the catalytic performance. The structure-activity correlation of both catalysts has also been revealed for automotive exhaust gas abatement. Results demonstrate that various copper species can be formed depending on the precursor-support interaction, affecting selectivity and conversion during the catalytic reaction.