In this study we compare the biodegradation of both single-walled (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) using two different oxidative conditions. In particular, we demonstrate that oxidized multi-walled carbon nanotubes are highly degraded, although not to completeness when treated with horseradish peroxidase (HRP) in the presence of hydrogen peroxide.

ANR (Nanorings imaging); CEA-Eurotalents progra

This review describes a wide panel of alkaloids isolated from plants of the Nitraria genus, focusing on their biosynthesis and discussing the resulting biomimetic chemistry in relevant cases. The scope is purposely limited to alkaloids derived at least to some extent from L-lysine, considering that most of these molecules have unique structures and are specific to the genus. Some of the biosynthetic pathways described are taken from the literature, but others are proposed here for the first time. The latter are mostly hypotheses justified by the fact that they are based on metabolic routes frequently encountered for other Nitraria alkaloids, and thus permit unification of the biosynthesis around common pivotal biosynthetic intermediates. Myrioneuron alkaloids are also presented as a newly discovered class with striking similarities to Nitraria alkaloids.

This concept article summarizes our recent findings regarding photopolymerized micelles obtained from the self-assembly of diacetylene-containing amphiphiles. Their synthesis and characterization are presented as well as some biomedical applications, such as tumor imaging and drug delivery. Finally, ongoing studies and future challenges are briefly discussed.

In vivo tumor targeting and drug delivery properties of small polymerized polydiacetylene (PDA) micelles (∼10 nm) is investigated in a murine MDA-MB-231 xenograft model of breast cancer. Three micelles with different surface coatings are synthesized and tested for their ability to passively target tumor through the enhanced permeability and retention effect. After injection (24 h), fluorescence diffuse optical tomographic imaging indicates a tumor uptake of nearly 3% of the injected dose for the micelles with a 2 kDa poly(ethylene glycol) (PEG)-coating (PDA-PEG2000). The uptake of PDA micelles in tumors is confirmed by co-localization with [(18) F]-fluorodeoxyglucose (FDG) positron emission tomography. Although FDG has a higher diffusion rate in tumors, 40 ± 19% of the retained micelles is co-registered with the tumor volume visualized by FDG. Finally, PDA-PEG2000 micelles are loaded with the hydrophobic anticancer drug paclitaxel and used in vivo to inhibit tumor growth. These findings demonstrate the potential of PDA-PEG2000 micelles for both in vivo tumor imaging and drug delivery applications.

Abioorthogonal approach is explored to release the content of nanoparticles on demand. Exploiting our recently described click-and-release technology,w ed eveloped an ew generation of cleavable micelles able to disassemble through as equential enzymatic and bioorthogonal activation process. Proof-of-concept experiments showed that this new approach could be successfully used to deliver the substances encapsulated into micelles in living cells as well as in mice by two complementary targeted strategies.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

With selected examples, we try to demonstrate that complex structures of natural products can be generated with surprising spontaneity. In such cases it appears that molecular complexity might emerge with minimal (if any) enzymatic assistance, through self‐construction mechanisms. Rearrangements of linear molecules, light‐induced reactions, dimerizations and multi‐component reactions could explain the formation of secondary metabolites through the intrinsic reactivity of their precursors. A few examples, amongst the most significant, are presented, along with efficient biomimetic syntheses that strengthen the hypotheses.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Rhodium nanoparticles were anchored on carbon nanotubes and the resulting nanohybrid was studied as co-catalyst, along with tert-butylcatechol, for the dehydrogenation of various N-heterocycles. The co-catalytic system operates in high yields, under the mildest conditions reported so far, and can be applied to a wide variety of secondary amine-containing scaffolds.