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PSL Chemical Biology Symposia: The Increasing Impact of Chemistry in Life Sciences
No full textInternational audienceThis symposium is the 6th Paris Sciences & Lettres (PSL) Chemical Biology meeting (2015, 2016, 2019, 2023, 2024, 2025) being held at Institut Curie. This initiative originally started in 2013 at Institut de Chimie des Substances Naturelles (ICSN) in Gif‐sur‐Yvette and was mostly focused on organic synthesis. It was then exported at Institut Curie to cover a larger scope, before becoming the official French Chemical Biology meeting. This year, around 200 participants had the opportunity to meet world leaders in chemistry and biology who described their latest innovations and future trends covering topics as diverse as prebiotic chemistry, activity‐based protein profiling, high‐resolution cell imaging, nanotechnologies, bio‐orthogonal chemistry, metal ion signaling, ferroptosis, and biocatalysis
Highly Sensitive Detection of Glucose in the Presence of Serum Based on Signal Amplification of Persistent Luminescence Nanoparticles Functionalized by Glucose Oxidase
No full textInternational audienceA new method is presented for the in vitro detection of glucose using glucose oxidase (GOx) covalently linked to persistent luminescent nanoparticles (PLNPs). This method ensures both sensitive and specific glucose detection by exploiting the enhanced luminescence of PLNPs in the presence of H 2 O 2 , generated by an enzymatic reaction. To this end, three different PLNPs composed of ZnGa 2 O 4 :Cr 3+ (ZGO) nanoparticles are prepared by hydrothermal synthesis at 120 °C for 6 h (ZGO1), 12 h (ZGO2), and 24 h (ZGO3), followed by a calcination at 500 °C, resulting in nanoparticles with an average hydrodynamic diameter of 100 nm ± 5 nm after grinding and centrifugation. These nanoparticles are efficiently covalently functionalized with GOx, via a PEG linker. Following the production of H 2 O 2 by the enzymatic reaction between GOx bound to the ZGO surface and glucose present in 100‐fold diluted serum, a significant increase in the persistent luminescent signal is observed. This phenomenon is most pronounced for ZGO2, for which a detection limit of 0.01 µ m and a detection range from 0.05 to 1 µ m is obtained. These results demonstrate the innovative potential of this new technique in glucose monitoring, opening up new avenues for real‐time monitoring and effective management of diabetes
Visible-Light-Mediated Radical Truce–Smiles Rearrangement via Arylazo Sulfones
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Poly(vinyl butyrate) Esters as Stable Polymer Matrix for Solid-State Li-Metal Batteries
No full textInternational audienceLi-metal-based batteries are considered as the next alternative to Li-ion batteries owing to their high specific capacity and energy density. Alleviating the use of liquid electrolytes, solid-state batteries using polymer electrolytes have gained vast attention. However, Li-metal solid-state batteries have major concerns regarding the non-total suppression of dendrites and high reactivity of the Li metal with certain polymers like polycaprolactones and polycarbonates, having main chain ester groups and which are considered as alternatives to PEO-based matrices. Herein we have designed a robust polymer matrix, namely, poly(vinyl butyrate) ester starting from a biodegradable polymer that is highly stable with Li metal, with appreciable ionic conductivity and single-ion conducting properties. A first approach has been made on these types of polymer matrices that not only introduces a modified polymer architecture for dry ester-based electrolytes but also shows unprecedented improvement in electrolyte performance with Li-metal polymer batteries
PIFA-mediated cyclization of methyl(2-(1-phenylvinyl)phenyl)sulfane for the concise, flexible, and scalable de novo synthesis of C3-arylated benzo[ b ]thiophenes
No full textInternational audienceThis work presents an efficient PIFA-mediated cyclization for synthesizing C3-arylated benzo[ b ]thiophenes, which are crucial in medicinal chemistry, while bypassing traditional sulfoxide intermediate formation via a novel thionium complex pathway
Couches minces d’oxydes de terres rares épitaxiées parCVD pour les technologies quantiques sur puce
No full textThe development of quantum technologies is generating great interest, as they promise major breakthroughs in computational power, measurement sensitivity and precision, as well as communication security, with potential applications acrossdiverse fields such as healthcare or electronics. In this context, rare-earth-doped oxide thin films represent a competitivesolid-state quantum platform for light–matter interactions. This is due to the ability of rare-earth ions to exhibit quantumcoherent states with long coherence times, combined with the nanometric thickness of the films, which makes them compatible with diverse photonic architectures. Chemical vapor deposition (CVD) offers a fast and cost-effective techniquefor producing thin films with good crystalline quality. However, compared to bulk crystals and ceramics, their propertiesare often degraded, likely due to surface proximity, a higher density of point defects, and strain. The use of epitaxial thinfilms, with a reduced defect density, is expected to lead to improved coherence times. The aim of this PhD project istherefore to obtain epitaxial CVD thin films and to enhance their crystalline properties in order to achieve light–matterinterfaces with long coherence times. Thin films were grown on various substrates, including silicon, oxides (quartz, sapphire, yttria-stabilized zirconia, YSZ), and hybrid substrates with a first layer deposited by molecular beam epitaxy (MBE).In parallel, the influence of post-deposition annealing treatments on the crystalline and optical properties of the films wasinvestigated. Epitaxy on hybrid substrates and YSZ was confirmed, with optical coherence times (T2) of 1.1 µs and 0.8µs, respectively, more than twenty times longer than those measured in polycrystalline films of equivalent composition.This epitaxial architecture paves the way for nanostructuring and integration into photonic devices such as resonators andwaveguides.Le développement des technologies quantiques suscite un fort intérêt, porté par les avancées majeures qu’elles promettent en termes de puissance de calcul, de sensibilité et précision de mesures, ou encore de sécurisation des communications, avec des applications possibles dans divers domaines tels que la santé, l’électronique etc. Dans ce contexte,les couches minces d’oxydes dopées aux ions de terres rares sont une plateforme quantique à l’état solide compétitivepour des interfaces lumière-matière. Ceci est dû, d’une part, à la capacité des ions de terres rares à présenter des étatsoptiques cohérents avec une très longue durée de vie, combiné à la dimension nanométrique des couches, les rendantcompatibles avec plusieurs types d’architectures photoniques. Le dépôt chimique en phase vapeur (CVD), offre ainsiune méthode de dépôt rapide et peu coûteuse de couches de bonne qualité cristalline. Cependant leurs propriétés sontsouvent dégradées par rapport à celles de cristaux massifs et céramiques, probablement en raison de la proximité de lasurface et de la présence de défauts ponctuels et de contraintes. L’utilisation de couches épitaxiées, comportant moins dedéfauts, pourrait donner lieu à des temps de cohérence optique améliorés. L’objectif de cette thèse est de fabriquer descouches épitaxiées par CVD et d’améliorer leurs propriétés cristallines afin d’obtenir des interfaces lumière-matière avecde longs temps de cohérence. Des dépôts ont été réalisés sur des substrats de diverses nature : silicium, oxydes (quartz,saphir, zircone yttriée - YSZ) et des substrats hybrides comportant une couche initiale réalisée par épitaxie à jet moléculaire (MBE). En parallèle, l’influence de post-traitements de recuit sur les propriétés cristallines et optiques des couches aété étudiée. L’épitaxie des couches sur un substrat hybride Gd2O3 sur silicium et sur YSZ a été confirmée avec des tempsde cohérence optique (T2) de 1,1 µs et 0,8 µs respectivement, soit des valeurs plus de vingt fois supérieures à celles pré-cédemment mesurées sur des couches polycristallines de composition équivalente. Cette architecture épitaxiale ouvrela voie à leur nanostructuration pour leur intégration dans des dispositifs photoniques tels que des résonateurs ou desguides d’ondes
Influence d'une pointe diélectrique sur la photophysique d'une molécule unique
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Unravelling the Stability Stressors of Atomically Dispersed Fe–N–C Oxygen Reduction Catalysts
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STARCH AND STARCH-HYDROXYAPATITE AEROGELS AND XEROGELS: HIERARCHICALLY STRUCTURED BIO-BASED MATERIALS FOR POTENTIALCANCELLOUS BONE REPAIR
No full textInternational audiencePorous starches are promising bio-based materials for biomedical use, notably as scaffolds and drug carriers. Potato starch gels were obtained via starch dissolution, retrogradation, solvent exchange and either supercritical drying CO₂ (aerogels) or evaporative drying (xerogels). Incorporating 100-200 µm hydroxyapatite (HA) based-beads produced porous starch-HA xerogels with preserved nanostructure, suitable for bone regeneration. Cytotoxicity tests confirmed material safety. 3Dprinting enabled hierarchical control, making these constructs viable candidates for cancellous bone substitutes
Corrosion evolution of aluminium-copper and aluminium-copper-lithium alloys in chloride solution
No full textInternational audienceThe objective of this work is to better understand the corrosion behavior of AA2024 (aluminium-copper) and AA2050 (aluminium-copper-lithium) alloys – used in aircraft fuselage and wings – by following their reactivity in a low-aggressive electrolyte (NaCl 0.01 M) using electrochemical and surface science techniques. It is shown that pitting is the predominant mode of corrosion, initiated at the locations where intermetallic particles were torn off from the surface during polishing. The growth of a corrosion product layer mainly composed of oxidized aluminium was monitored over 72 hours of immersion in the electrolyte using X-ray Photoelectron Spectroscopy (XPS) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) analyses. It is revealed that lithium increases the alloy’s thermodynamic susceptibility to corrosion but leads to reduction of the kinetic corrosion rate by promoting the formation of a more homogeneous corrosion product layer. Additionally, it is shown that the mechanism evolves over time. During the first hours of immersion, the limiting reaction is the charge transfer between the metallic substrate and the electrolyte, whereas at longer immersion times, it becomes the diffusion of the dissolved dioxygen from the electrolyte into the growing oxide layer