jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Jorge Faiges | Maria Biosca | Miquel À. Pericàs | María Besora | Òscar Pàmies | Montserrat Diéguez
Source: Angewandte Chemie International Edition (article, 2023-12-14)
Field: Chemistry — Inorganic Chemistry

Unlocking the Asymmetric Hydrogenation of Tetrasubstituted Acyclic Enones Asymmetric hydrogenation (AH) of tetrasubstituted olefins generating two stereocenters is still an open topic. There are only a few reports on the AH of tetrasubstituted olefins with conjugated functional groups, while this process can create useful intermediates for the subsequent elaboration of relevant end products. Most of the tetrasubstituted olefins successfully submitted to AH belong to a small number of functional classes; remarkably, the AH of tetrasubstituted acyclic enones still represents an unsolved challenge. Herein, we disclose a class of air-stable Ir-P,N catalysts, prepared in three steps from commercially available amino alcohols, that can hydrogenate, in minutes, a wide range of electronically and sterically diverse acyclic tetrasubstituted enones (including exocyclic ones) with high yields and high enantioselectivities. The factors responsible for the excellent selectivities were elucidated by combining deuterogenation experiments and theoretical calculations. The calculations indicated that the reduction follows an Ir<sup>I</sup> /Ir<sup>III</sup> mechanism, in which enantioselectivity is controlled in the first migratory insertion of the hydride to the most electrophilic olefinic C<sub>β</sub> and the formation of the hydrogenated product via reductive elimination takes place prior to the coordination of dihydrogen and the subsequent oxidative addition. The potential of the new catalytic systems is demonstrated by the derivatization of hydrogenation products. Stereocenter ; Chemistry ; Electrophile ; Steric effects ; Hydride ; Combinatorial chemistry ; Catalysis ; Conjugated system ; Chemoselectivity ; Organic chemistry ; Enantioselective synthesis ; Hydrogen Asymmetric Hydrogenation and Catalysis ; Catalysis and Hydrodesulfurization Studies ; Surface Chemistry and Catalysis
Authors: Peiyuan Gao | Scott E. Muller | Jaehun Chun | Lirong Zhong | Zachary C. Kennedy
Source: Polymer (article, 2023-01-17)
Field: Materials Science — Polymers and Plastics

Effects of 2D filler on rheology of additive manufacturing polymers: Simulation and experiment on polyetherketoneketone-mica composites Rheology ; Materials science ; Filler (materials) ; Composite material ; Polymer ; Composite number ; Viscosity ; Mica ; Shear rate Polymer Nanocomposites and Properties ; Polymer crystallization and properties ; Carbon Nanotubes in Composites
Authors: Arnon Fluksman | Aritz Lafuente | Ron Braunstein | Eliana Steinberg | Nethanel Friedman | Zhanna Yekhin | Alejandro G. Roca | J. Nogués | Ronen Hazan | Borja Sepúlveda | Ofra Benny
Source: ACS Applied Materials & Interfaces (article, 2023-10-20)
Field: Materials Science — Biomaterials

Modular Drug-Loaded Nanocapsules with Metal Dome Layers as a Platform for Obtaining Synergistic Therapeutic Biological Activities Multifunctional drug-loaded polymer-metal nanocapsules have attracted increasing attention in drug delivery due to their multifunctional potential endowed by drug activity and response to physicochemical stimuli. Current chemical synthesis methods of polymer/metal capsules require specific optimization of the different components to produce particles with precise properties, being particularly complex for Janus structures combining polymers and ferromagnetic and highly reactive metals. With the aim to generate tunable synergistic nanotherapeutic actuation with enhanced drug effects, here we demonstrate a versatile hybrid chemical/physical fabrication strategy to incorporate different functional metals with tailored magnetic, optical, or chemical properties on solid drug-loaded polymer nanoparticles. As archetypical examples, we present poly(lactic-<i>co</i>-glycolic acid) (PLGA) nanoparticles (diameters 100-150 nm) loaded with paclitaxel, indocyanine green, or erythromycin that are half-capped by either Fe, Au, or Cu layers, respectively, with application in three biomedical models. The Fe coating on paclitaxel-loaded nanocapsules permitted efficient magnetic enhancement of the cancer spheroid assembly, with 40% reduction of the cross-section area after 24 h, as well as a higher paclitaxel effect. In addition, the Fe-PLGA nanocapsules enabled external contactless manipulation of multicellular cancer spheroids with a speed of 150 μm/s. The Au-coated and indocyanine green-loaded nanocapsules demonstrated theranostic potential and enhanced anticancer activity in vitro and in vivo due to noninvasive fluorescence imaging with long penetration near-infrared (NIR) light and simultaneous photothermal-photodynamic actuation, showing a 3.5-fold reduction in the tumor volume growth with only 5 min of NIR illumination. Finally, the Cu-coated erythromycin-loaded nanocapsules exhibited enhanced antibacterial activity with a 2.5-fold reduction in the MIC50 concentration with respect to the free or encapsulated drug. Altogether, this technology can extend a nearly unlimited combination of metals, polymers, and drugs, thus enabling the integration of magnetic, optical, and electrochemical properties in drug-loaded nanoparticles to externally control and improve a wide range of biomedical applications. Nanocapsules ; Materials science ; PLGA ; Nanotechnology ; Polymer ; Nanoparticle ; Photothermal therapy ; Drug delivery ; Indocyanine green ; Paclitaxel ; Chemical engineering ; Composite material Nanoparticle-Based Drug Delivery ; Micro and Nano Robotics ; Nanoplatforms for cancer theranostics
Authors: Yue Wu | Rongji Tang | Anfu Guo | Xiaodong Tao | Yingbin Hu | Xianliang Sheng | Peng Qu | Shaoqing Wang | Jianfeng Li | Fangyi Li
Source: Materials (article, 2023-08-30)
Field: Materials Science — Biomaterials

Enhancing Starch−Based Packaging Materials: Optimization of Plasticizers and Process Parameters In order to actively promote green production and address these concerns, there is an urgent need for new packaging materials to replace traditional plastic products. Starch-based packaging materials, composed of starch, fiber, and plasticizers, offer a degradable and environmentally friendly alternative. However, there are challenges related to the high crystallinity and poor compatibility between thermoplastic starch and fibers, resulting in decreased mechanical properties. To address these challenges, a novel approach combining plasticizer optimization and response surface method (RSM) optimization has been proposed to enhance the mechanical properties of starch-based packaging materials. This method leverages the advantages of composite plasticizers and process parameters. Scanning electron microscopy and X-ray crystallography results demonstrate that the composite plasticizer effectively disrupts the hydrogen bonding and granule morphology of starch, leading to a significant reduction in crystallinity. Fourier transform infrared spectroscopy results show that an addition of glycerol and D-fructose to the starch can form new hydrogen bonds between them, resulting in an enhanced plasticizing effect. The optimal process parameters are determined using the RSM, resulting in a forming temperature of 198 °C, a forming time of 5.4 min, and an AC content of 0.84 g. Compared with the non-optimized values, the tensile strength increases by 12.2% and the rebound rate increases by 8.1%. Plasticizer ; Materials science ; Crystallinity ; Starch ; Thermoplastic ; Response surface methodology ; Fourier transform infrared spectroscopy ; Composite number ; Composite material ; Ultimate tensile strength ; Glycerol ; Chemical engineering ; Chemistry ; Organic chemistry ; Chromatography biodegradable polymer synthesis and properties ; Nanocomposite Films for Food Packaging ; Advanced Cellulose Research Studies
Authors: Frederik Peschke | Andrea Taladriz‐Sender | Matthew J. Andrews | Allan J. B. Watson | Glenn A. Burley
Source: Angewandte Chemie International Edition (article, 2023-10-31)
Field: Chemistry — Organic Chemistry

Glutathione Mediates Control of Dual Differential Bio‐orthogonal Labelling of Biomolecules Traditional approaches to bio-orthogonal reaction discovery have focused on developing reagent pairs that react with each other faster than they are metabolically degraded. Glutathione (GSH) is typically responsible for the deactivation of most bio-orthogonal reagents. Here we demonstrate that GSH promotes a Cu-catalysed (3+2) cycloaddition reaction between an ynamine and an azide. We show that GSH acts as a redox modulator to control the Cu oxidation state in these cycloadditions. Rate enhancement of this reaction is specific for ynamine substrates and is tuneable by the Cu:GSH ratio. This unique GSH-mediated reactivity gradient is then utilised in the dual sequential bio-orthogonal labelling of peptides and oligonucleotides via two distinct chemoselective (3+2) cycloadditions. Glutathione ; Chemistry ; Cycloaddition ; Reagent ; Combinatorial chemistry ; Biomolecule ; Labelling ; Reactivity (psychology) ; Redox ; Azide ; Organic chemistry ; Biochemistry ; Enzyme ; Catalysis Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Biotin and Related Studies
Authors: Eleonora Truzzi | Davide Bertelli | Anna Rita Bilia | Giulia Vanti | Eleonora Maretti | Eliana Leo
Source: Pharmaceutics (review, 2023-11-11)
Field: Materials Science — Biomaterials

Combination of Nanodelivery Systems and Constituents Derived from Novel Foods: A Comprehensive Review Novel Food is a new category of food, regulated by the European Union Directive No. 2015/2283. This latter norm defines a food as "Novel" if it was not used "for human consumption to a significant degree within the Union before the date of entry into force of that regulation, namely 15 May 1997". Recently, Novel Foods have received increased interest from researchers worldwide. In this sense, the key areas of interest are the discovery of new benefits for human health and the exploitation of these novel sources of materials in new fields of application. An emerging area in the pharmaceutical and medicinal fields is nanotechnology, which deals with the development of new delivery systems at a nanometric scale. In this context, this review aims to summarize the recent advances on the design and characterization of nanodelivery systems based on materials belonging to the Novel Food list, as well as on nanoceutical products formulated for delivering compounds derived from Novel Foods. Additionally, the safety hazard of using nanoparticles in food products, i.e., food supplements, has been discussed in view of the current European regulation, which considers nanomaterials as Novel Foods. European union ; Context (archaeology) ; Human health ; Food products ; Biotechnology ; Risk analysis (engineering) ; Directive ; Food safety ; Business ; Nanotechnology ; Computer science ; Medicine ; Environmental health ; Biology ; International trade ; Food science Nanocomposite Films for Food Packaging ; Proteins in Food Systems ; Protein Hydrolysis and Bioactive Peptides
Authors: Alexander Kastner | Theresa Mendrina | Tomer Babu | Subhendu Karmakar | Isabella Poetsch | Walter Berger | Bernhard K. Keppler | Dan Gibson | Petra Heffeter | Christian R. Kowol
Source: Inorganic Chemistry Frontiers (article, 2023-12-06)
Field: Materials Science — Biomaterials

Stepwise optimization of tumor-targeted dual-action platinum(<scp>iv</scp>)-gemcitabine prodrugs While platinum-based chemotherapeutic agents have established themselves as indispensable components of anticancer therapy, they are accompanied by a variety of side effects and the rapid occurrence of drug resistance. A promising strategy to address these challenges is the use of platinum(iv) prodrugs, which remain inert until they reach the tumor tissue, thereby mitigating detrimental effects on healthy cells. Typically, platinum drugs are part of combination therapy settings. Consequently, a very elegant strategy is the development of platinum(iv) prodrugs bearing a second, clinically relevant therapeutic in axial position. In the present study, we focused on gemcitabine as an approved antimetabolite, which is highly synergistic with platinum drugs. In addition, to increase plasma half-life and facilitate tumor-specific accumulation, an albumin-binding maleimide moiety was attached. Our investigations revealed that maleimide-cisplatin(iv)-gemcitabine complexes cannot carry sufficient amounts of gemcitabine to induce a significant effect <i>in vivo</i>. Consequently, we designed a carboplatin(iv) analog, that can be applied at much higher doses. Remarkably, this novel analog demonstrated impressive <i>in vivo</i> results, characterized by significant improvements in overall survival. Notably, these encouraging results could also be transferred to an <i>in vivo</i> xenograft model with acquired gemcitabine resistance, indicating the high potential of this approach. Gemcitabine ; Prodrug ; Platinum ; Dual (grammatical number) ; Chemistry ; Pharmacology ; Cancer research ; Biochemistry ; Medicine ; Internal medicine ; Cancer ; Catalysis ; Philosophy Nanoparticle-Based Drug Delivery ; Metal complexes synthesis and properties ; Radiopharmaceutical Chemistry and Applications
Authors: Naveen Shetty | Hans He | Richa Mitra | Johanna Huhtasaari | Konstantina Iordanidou | Julia Wiktor | Sergey Kubatkin | Saroj P. Dash | Rositsa Yakimova | Lunjie Zeng | Eva Olsson | Samuel Lara‐Avila
Source: ACS Applied Nano Materials (article, 2023-03-30)
Field: Materials Science — Materials Chemistry

Scalable Fabrication of Edge Contacts to 2D Materials: Implications for Quantum Resistance Metrology and 2D Electronics We report a reliable and scalable fabrication method for producing electrical contacts to two-dimensional (2D) materials based on the tri-layer resist system. We demonstrate the applicability of this method in devices fabricated on epitaxial graphene on silicon carbide (epigraphene) used as a scalable 2D material platform. For epigraphene, data on nearly 70 contacts result in median values of the one-dimensional (1D) specific contact resistances ρc ∼ 67 Ω·μm and follow the Landauer quantum limit ρc ∼ n–1/2, consistently reaching values ρc < 50 Ω·μm at high carrier densityn. As a proof of concept, we apply the same fabrication method to the transition metal dichalcogenide (TMDC) molybdenum disulfide (MoS2). Our edge contacts enable MoS2 field-effect transistor (FET) behavior with an ON/OFF ratio of >106 at room temperature (>109 at cryogenic temperatures). The fabrication route demonstrated here allows for contact metallization using thermal evaporation and also by sputtering, giving an additional flexibility when designing electrical interfaces, which is key in practical devices and when exploring the electrical properties of emerging materials. Fabrication ; Materials science ; Graphene ; Contact resistance ; Nanotechnology ; Optoelectronics ; Electronics ; Electrical contacts ; Transistor ; Layer (electronics) ; Electrical engineering ; Voltage Graphene research and applications ; 2D Materials and Applications ; Nanowire Synthesis and Applications
Authors: Akanksha Ashok Sangolkar | Rama Krishna Kadiyam | Ravinder Pawar
Source: Energy Advances (article, 2023-11-28)
Field: Materials Science — Materials Chemistry

Aza-bicyclodiene based photoswitches for molecular solar thermal energy storage The effect of N -substitution on the properties of bicyclodienes with different bridge lengths is analysed for energy storage application. The improvement in the properties with N -substitution is more prominent for bicyclodienes with longer bridge. Substitution (logic) ; Thermal energy storage ; Energy storage ; Thermal ; Materials science ; Bridge (graph theory) ; Nanotechnology ; Physics ; Thermodynamics ; Computer science Photochromic and Fluorescence Chemistry ; Porphyrin and Phthalocyanine Chemistry ; TiO2 Photocatalysis and Solar Cells
Authors: Paola Rubiano-Buitrago | Shrikant Pradhan | Veit Grabe | Alfonso Aceves‐Aparicio | Christian Paetz | Hannah M. Rowland
Source: Frontiers in Ecology and Evolution (article, 2023-06-08)
Field: Materials Science — Biomaterials

Differential accumulation of cardenolides from Asclepias curassavica by large milkweed bugs does not correspond to availability in seeds or biological activity on the bug Na+/K+-ATPase Milkweed–herbivore systems are characterized by cardenolide chemical defenses and specialized herbivore adaptations such as physiological target site insensitivity. Cardenolide defenses in milkweeds can vary in terms of the total concentration, differences in the polarity of individual cardenolides, and the substitution of the steroidal structures that can contribute to the molecule's reactivity. The variability in cardenolide defenses could represent the plant's response to natural selection and adaptation of resistant herbivores and is a characteristic of phenotype-matching between defensive and offensive traits resulting from coevolution. Here, we test the phenotypic match of the cardenolide composition of seeds of Asclepias curassavica and those sequestered by nymphs and adults of the specialized seed herbivore Oncopeltus fasciatus , combined with tests of the inhibitory capacity of a subset of seed cardenolides against the Na + /K + -ATPase of O. fasciatus and a non-adapted insect ( Drosophila melanogaster ). We compare this with the inhibitory capacity against the highly sensitive porcine Na + /K + -ATPase. Among the five most abundant cardenolides present in milkweed seeds, glucopyranosyl frugoside, glucopyranosyl gofruside, and glucopyranosyl calotropin were significantly more abundant in the seeds than in the adults and nymphs; the bugs contained higher concentrations of the deglucosylated compounds. The most abundant compound, glucopyranosyl frugoside, was also the most inhibitory for O. fasciatus , but O. fasciatus was significantly more tolerant to all compounds compared to D. melanogaster and the highly sensitive porcine enzyme. Our results add to the evidence that O. fasciatus sequesters specific individual cardenolides from its Asclepias host plants that are not directly linked to the concentration and inhibitory potency. Cardenolide ; Biology ; Chemical defense ; Botany ; Herbivore ; Insect ; Monarch butterfly ; Chemical ecology ; Glycoside Phytochemistry and Bioactive Compounds ; Phytochemical compounds biological activities ; Neurobiology and Insect Physiology Research
Authors: Yingying Cai | Philipp Vana
Source: Angewandte Chemie International Edition (article, 2023-08-14)
Field: Materials Science — Electronic, Optical and Magnetic Materials

2D Plasmonic Molecules via Hydrogen Bond Interaction between Polymer‐Grafted Nanoparticles The use of macromolecular design features to regulate non-covalent bonding on the nanoscale is a young and emerging fabrication strategy for advanced nanostructures. For the first time, we describe a self-assembly method to create a series of 2D plasmonic molecules (PMs) using hydrogen-bond interaction between a pair of polymer-capped gold nanoparticles (hydrogen-bond donor and acceptor). Due to the nature of hydrogen-bond interaction, we found that polymer interaction and solvation compete with each other during the self-assembly process, which turns out to be the most important condition for controlling the coordination number of PMs. We have conducted an extensive study on the solvent effect, which has helped us to design and fabricate a series of precise PMs with high symmetry. Hydrogen bond ; Molecule ; Covalent bond ; Polymer ; Materials science ; Solvation ; Nanoparticle ; Nanotechnology ; Nanostructure ; Acceptor ; Plasmon ; Fabrication ; Chemical physics ; Self-assembly ; Chemistry ; Organic chemistry ; Optoelectronics ; Physics Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Pickering emulsions and particle stabilization
Authors: Pavel Valencia-Acuña | Fatimah Rudayni | Kushal Rijal | Wai‐Lun Chan | Hui Zhao
Source: ACS Nano (article, 2023-02-16)
Field: Materials Science — Materials Chemistry

Hybrid Heterostructures to Generate Long-Lived and Mobile Photocarriers in Graphene We report the generation of long-lived and highly mobile photocarriers in hybrid van der Waals heterostructures that are formed by monolayer graphene, few-layer transition metal dichalcogenides, and the organic semiconductor F<sub>8</sub>ZnPc. Samples are fabricated by dry transfer of mechanically exfoliated MoS<sub>2</sub> or WS<sub>2</sub> few-layer flakes on a graphene film, followed by deposition of F<sub>8</sub>ZnPc. Transient absorption microscopy measurements are performed to study the photocarrier dynamics. In heterostructures of F<sub>8</sub>ZnPc/few-layer-MoS<sub>2</sub>/graphene, electrons excited in F<sub>8</sub>ZnPc can transfer to graphene and thus be separated from the holes that reside in F<sub>8</sub>ZnPc. By increasing the thickness of MoS<sub>2</sub>, these electrons acquire long recombination lifetimes of over 100 ps and a high mobility of 2800 cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup>. Graphene doping with mobile holes is also demonstrated with WS<sub>2</sub> as the middle layers. These artificial heterostructures can improve the performance of graphene-based optoelectronic devices. Graphene ; Heterojunction ; Materials science ; Monolayer ; Electron mobility ; Optoelectronics ; Semiconductor ; Doping ; van der Waals force ; Nanotechnology ; Layer (electronics) ; Electron transfer ; Chemistry ; Photochemistry ; Molecule 2D Materials and Applications ; Graphene research and applications ; Nanowire Synthesis and Applications
Authors: Marco Ferrari | Gianluca Boccardo | Daniele Marchisio | Antonio Buffo
Source: AIP Advances (article, 2023-03-01)
Field: Materials Science — Materials Chemistry

Application of dissipative particle dynamics to interfacial systems: Parameterization and scaling Dissipative Particle Dynamics (DPD) is a stochastic particle model that is able to simulate larger systems over longer time scales than atomistic modeling approaches by including the concept of coarse-graining. Whether standard DPD can cover the whole mesoscale by changing the level of coarse-graining is still an open issue. A scaling scheme originally developed by Füchslin et al. (2009) was here applied to interfacial systems as one of the most successful uses of the classical DPD method. In particular, equilibrium properties such as the interfacial tension were analyzed at different levels of coarse-graining for planar oil–water interfaces with and without surfactant. A scaling factor for the interfacial tension was found due to the combined effect of the scaling scheme and the coarse-graining parameterization. Although the level of molecular description was largely decreased, promising results showed that it is possible to conserve the interfacial tension trend at increasing surfactant concentrations, remarkably reducing modeling complexity. The same approach was also employed to simulate a droplet configuration. Both planar and droplet conformations were maintained, showing that typical domain formations of multi-component systems can be performed in DPD by means of the scaling procedure. Therefore, we explored the possibility of describing oil–water and oil–water–surfactant systems in standard DPD using a scaling scheme with the aim of highlighting its advantages and limitations. Dissipative particle dynamics ; Scaling ; Granularity ; Surface tension ; Statistical physics ; Molecular dynamics ; Particle (ecology) ; Pulmonary surfactant ; Planar ; Dissipative system ; Chemical physics ; Materials science ; Physics ; Thermodynamics ; Chemistry ; Computer science ; Mathematics ; Computational chemistry ; Polymer Block Copolymer Self-Assembly ; Surfactants and Colloidal Systems ; Polymer Surface Interaction Studies