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Deep-eutectic solvent as a solvent and precursor for the synthesis of a carbon-coated Na3V2(PO4)2F3–yOy material
No full text"ADC - Accord Couperin / American Chemical Society (2024-2026)"International audienceDeep eutectic solvents (DES) are well-known as cost-effective and environmentally friendly “designer solvents” for controlling the size and morphology of nanomaterials. In this study, we leverage DES not only as a solvent for the topochemical synthesis of Na3V2(PO4)2F3–yOy (0 ≤ y ≤ 2) but also as a precursor for a uniform and thin carbon coating. After solvothermal synthesis in a green deep eutectic solvent composed of a mixture of choline chloride, citric acid, and water (3:1:3 molar ratio), XRD refinements and FTIR, XPS, and TEM analyses confirmed the obtention of a pure Na3V2(PO4)2F3–yOy (0 ≤ y ≤ 2) phase encapsulated in an organic layer derived from a residual deep eutectic solvent. Subsequent sintering at 600 °C under an argon atmosphere produced a homogeneous nitrogen-doped carbon coating without the need for additional carbon sources. Electrochemical tests in galvanostatic conditions demonstrated that this material exhibits excellent performance in terms of capacity retention and rate capabilities, with specific capacities exceeding 110 mAh/g at 2C versus Na metal and 68 mAh/g at 10C in full cells versus hard carbon
Nanoconfinement‐Induced Electrochemical Ion‐Solvent Cointercalation in Pillared Titanate Host Materials
No full textInternational audienceAbstract Electrochemical ion‐solvent cointercalation reactions are an avenue to reach improved kinetics compared to the corresponding intercalation of desolvated ions. Here, we demonstrate the impact of different structural pillar molecules on the electrochemical Li + intercalation mechanism in expanded hydrogen titanate (HTO) electrode materials. We show that interlayer‐expansion of HTO with organic pillars can enable cointercalation reactions. Their electrochemical reversibility is drastically improved when non‐cross‐linking pillars are employed that expand and separate the host material's individual layers, underlining the impact of the electrochemo‐mechanics of the nanoconfined interlayer space. This pillared HTO structure results in an increased Li + storage capacity and reversibility compared to pristine HTO. We derive structural models of the pillared HTO host materials based on combined experiments and theoretical calculations, and employ electrochemical operando experiments to unambiguously demonstrate the nanoconfinement‐induced cointercalation mechanism in pillared HTO electrode materials. The work demonstrates the potential of nanoconfined pillar molecules to modify host materials and enable highly reversible cointercalation reactions with improved capacity and kinetics
Synthetic strategies for the incorporation of metallocenes into anti-infective scaffolds
No full textInternational audienceWith the rates of infectious diseases and (pan)drug-resistant pathogens constantly increasing, there is a pressing need for the development of new drug candidates. To fight this global health crisis, new medicines should propose improved or novel modes of action. A successful strategy to fight microbial resistance is the incorporation of metallocenes into drug scaffolds. This review aims at encouraging the scientific community to follow this approach by giving an overview of all published synthetic strategies either for the derivatization of anti-infective drug scaffolds with metallocenes or for the de novo synthesis of original metallocenyl anti-infectives. This should facilitate future research as published articles are classified depending on the reaction type that is employed for the incorporation of the metallocenes, namely addition–elimination, condensation, “click” chemistry, cross-coupling, nucleophilic substitution and other methods. Overall, this review exhibits the impressive but somewhat unexploited potential of anti-infective metallocenyl compounds to treat infectious diseases
In‐Situ Constructing Eosin Y Sensitized Cs<sub>2</sub>PtSnCl<sub>6</sub> Perovskites for Enhanced Photocatalytic Hydrogen Evolution
No full textInternational audienceVacancy‐ordered Cs2SnX6 perovskites, with low‐toxicity and high stability, have emerged as promising photocatalysts for hydrogen evolution reaction (HER). However, most Cs2SnX6 and derivatives have low catalytic activity mainly due to their insufficient light utilization efficiency. Herein, a simple in situ method is introduced to sensitize Cs2PtSnCl6 with Eosin Y (EY), forming EY‐Cs2PtSnCl6 for HER in aqueous solution. Various characterizations indicate that the EY is immobilized onto the Cs2PtSnCl6 during the synthesis process. The EY‐Cs2PtSnCl6 displayed extended light absorption range and efficient charge transfer from EY to Cs2PtSnCl 6 . The resulting EY‐Cs2PtSnCl6 material exhibits high HER rate of 17.6 mmol g−1 h−1, ≈1760 folds than that of the pristine Cs2PtSnCl6. This work demonstrates an effective method to construct dye‐sensitized perovskites and highlights the importance of interaction between dye and perovskite. It provides useful guidance for the design of new perovskite‐based photocatalysts and it will advance the development of perovskites for solar energy conversion into renewable fuels
Ruthenium(II) Polypyridyl Complexes Containing COUBPY Ligands as Potent Photosensitizers for the Efficient Phototherapy of Hypoxic Tumors
No full textInternational audienceHypoxia, a hallmark of many solid tumors, is linked to increased cancer aggressiveness, metastasis, and resistance to conventional therapies, leading to poor patient outcomes. This challenges the efficiency of photodynamic therapy (PDT), which relies on the generation of cytotoxic reactive oxygen species (ROS) through the irradiation of a photosensitizer (PS), a process partially dependent on oxygen levels. In this work, we introduce a novel family of potent PSs based on ruthenium(II) polypyridyl complexes with 2,2'-bipyridyl ligands derived from COUPY coumarins, termed COUBPYs. Ru(II)-COUBPY complexes exhibit outstanding in vitro cytotoxicity against CT-26 cancer cells when irradiated with light within the phototherapeutic window, achieving nanomolar potency in both normoxic and hypoxic conditions while remaining nontoxic in the dark, leading to impressive phototoxic indices (>30,000). Their ability to generate both Type I and Type II ROS underpins their exceptional PDT efficiency. The lead compound of this study, SCV49, shows a favorable in vivo pharmacokinetics profile, excellent toxicological tolerability, and potent tumor growth inhibition in mice bearing subcutaneous CT-26 tumors at doses as low as 3 mg/kg upon irradiation with deep-red light (660 nm). These results allow to propose SCV49 as a strong candidate for further preclinical development, particularly for treating large hypoxic solid tumors.</div
Cytotoxic Ruthenium(II)‐diphosphine Complexes affect the Mitochondrial Respiration of Lung Cancer Cells
No full textInternational audienceIn this work, we studied six Ruthenium(II)‐diphosphine compounds containing different mercapto ligands (N–S), with general formula [Ru(N–S)(dppm)2]Cl (dppm = 1,1‐bis(diphenylphosphino)methane). These compounds were characterized by several techniques (NMR [1H, 31P(1H), and 13C], HRMS, IR, UV‐Vis and XRD) and their purity confirmed by elemental analysis. DLS experiments revealed low diameters and polydispersity indexes, and positive log P values in n‐octanol/PBS indicated their preference for the organic phase. In general, these compounds are stable in different media over 48 h. Cytotoxicity experiments revealed promising IC50 values on A549 breast cancer cells, 0.48 µM and 0.80 µM for [Ru(mtz)(dppm)2]Cl (1) and [Ru(mmi)(dppm)2]Cl (2), respectively (mtz and mmi are 2‐mercapto‐2‐thiazoline and mercapto‐1‐methylimidazole in their deprotonated form, respectively). Clonogenic and migration experiments indicated their antiproliferative and anti‐migratory capacity. ICP‐MS results indicated their cellular accumulation in the nucleus, with little amounts in mitochondria. No covalent DNA binding was observed by ICP‐MS. JC‐1 and cell Mito Stress test confirmed mitochondrial dysfunction, which was verified by mitochondrial membrane potential uncoupling and drastic alterations in the oxygen consumption rate. Taken together, our results provide crucial insights regarding the anticancer potential of ruthenium(II)‐phosphine compounds
Physics-assisted machine learning for slurry drying simulation in manufacturing process of battery electrodes: A hybrid time-dependent VGG16-DEM model
No full textIn this study, we present a hybrid Physics-Assisted Machine Learning (PAML) model that integrates Deep Learning (DL) techniques with the classical Discrete Element Method (DEM) to simulate the slurry drying during a lithium ion battery electrode manufacturing process. This model predicts the microstructure evolution leading to the formation of the electrode, as a time-series along the drying process. The hybrid approach consists in performing a certain amount of DEM simulation steps, n_DEM, after every DL prediction, mitigating the risk of unphysical predictions, like overlapping particles. Our PAML model was rigorously tested by evaluating different functional metrics of the predicted electrodes, including density, porosity, tortuosity factor, and radial distribution function. We conducted an in-depth analysis of performance versus accuracy, particularly focusing on the impact of the n_DEM hyperparameter, which represents the number of DEM steps executed between two subsequent DL predictions. Despite the model being trained on a specific formulation (96% of Active Material, AM, and 4% of Carbon Binder Domain, CBD), it demonstrated exceptional generalization capability when used to extrapolate to a different formulation (94% AM and 6% CBD). This adaptability highlights the robustness of our PAML hybrid approach. Furthermore, the integration of DL significantly reduced the computational cost of the original DEM model, decreasing the processing time from 34.2 minutes per step to approximately 2 minutes per step. Our findings underscore the potential of combining ML with traditional simulation methods to enhance efficiency and accuracy in the field of electrode manufacturing
Chemical dissection of selective myeloid leukemia-1 inhibitors: How they were found and evolved
No full textInternational audienceMyeloid cell leukemia-1 (MCL-1), a key anti-apoptotic protein within the BCL-2 family, is essential in regulating cell survival, particularly in cancer, where its overexpression is often linked to therapeutic resistance. This review begins with an overview of BCL-2-mediated apoptosis, highlighting the pivotal role of MCL-1 in cellular homeostasis. We then focus on the structure and function of MCL-1, elucidating how its unique structural features contribute to its function and interaction with pro-apoptotic proteins. The core of this review is a detailed structural analysis of selective MCL-1 inhibitors, tracing their development from initial discovery to stepwise optimization.We explore various classes of inhibitors, including those with distinct core structures, covalent inhibitors that reversibly/irreversibly bind to MCL-1, and innovative approaches such as metal-based inhibitors and proteolysis-targeting chimeras (PROTACs). The structural evolution of these inhibitors is discussed, with particular emphasis on the modifications that have enhanced their selectivity, potency, and pharmacokinetic profiles. Additionally, we summarize the synergistic potential of MCL-1 inhibitors when used in combination with other therapeutic agents, emphasizing their role in overcoming drug resistance. The review concludes with a discussion of current challenges in MCL-1 modulation and future perspectives, proposing alternative strategies for targeting this critical protein for cancer therapy.</p
: Laudatio: Miguel Julve et Francisco Lloret, une paire amicale de deux chimistes de coordination exceptionnels en magnétisme moléculaire
No full textInternational audienceThis laudatio is dedicated to Professors Miguel Julve Olcina and Francisco Lloret Pastor on the occasion of their retirement in 2024. The first part deals with the scientific trajectory of the Coordination Chemistry team at the University of Valencia, within the Department of Inorganic Chemistry on the Burjassot campus and then in the Paterna Institute of Molecular Science. The second part relates some of the more salient results of the heritage left by our two colleagues in molecular magnetism, where they developed, in their own way, a rational approach to designing, creating and understanding a wealth of brand new systems from the simplest to Multifunctional Molecule-based Magnetic Materials. The robust and friendly links between our two colleagues are emphasized in the third part
Study of charge transport limitations in lithium-ion battery electrodes
No full textInternational audienc