jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Fengrong Zhang | Teoman Benli‐Hoppe | Wei Guo | Johanna Seidl | Yi Wang | Rongqin Huang | Ernst Wagner
Source: Polymers (article, 2023-10-10)
Field: Materials Science — Materials Chemistry

Receptor-Targeted Carbon Nanodot Delivery through Polymer Caging and Click Chemistry-Supported LRP1 Ligand Attachment Carbon nanodots present resistance to photobleaching, bright photoluminescence, and superior biocompatibility, making them highly promising for bioimaging applications. Herein, nanoprobes were caged with four-armed oligomers and subsequently modified with a novel DBCO-PEG-modified retro-enantio peptide ligand reL57, enhancing cellular uptake into U87MG glioma cells highly expressing low-density lipoprotein receptor-related protein 1 (LRP1). A key point in the development of the oligomers was the incorporation of ε-amino-linked lysines instead of standard α-amino-linked lysines, which considerably extended the contour length per monomer. The four-armed oligomer <b><i>1696</i></b> was identified as the best performer, spanning a contour length of ~8.42 nm for each arm, and was based on an altering motive of two cationic ε-amidated lysine tripeptides and two tyrosine tripeptides for electrostatic and aromatic stabilization of the resulting formulations, cysteines for disulfide-based caging, and N-terminal azidolysines for click-modification. This work highlights that well-designed four-armed oligomers can be used for noncovalent coating and covalent caging of nanoprobes, and click modification using a novel LRP1-directed peptide ligand facilitates delivery into receptor-expressing target cells. Chemistry ; Click chemistry ; Ligand (biochemistry) ; Monomer ; Polylysine ; Tripeptide ; Biophysics ; Combinatorial chemistry ; Peptide ; Polymer ; Receptor ; Biochemistry ; Organic chemistry Carbon and Quantum Dots Applications ; Nanocluster Synthesis and Applications ; Electrochemical sensors and biosensors
Authors: Preeti Devi | Vikas Budhwar | Saloni Kakkar | Ashwani Kumar
Source: International Journal of Life Science and Pharma Research (article, 2023-11-01)
Field: Materials Science — Materials Chemistry

Pharmaceutical Co-Crystallization: Strategies for Co-Crystal Design Pharmaceutical co-crystal belongs to a subtype of crystal in which one component is an active pharmaceutical ingredient (API) and the other is coformer (generally regarded as safe GRAS). In the crystal lattice, the two components are hydrogen-bonded in a fixed stoichiometric ratio. Co-crystallization is a cheap and simple alternative to the presently available techniques of solubility enhancement and has gained much interest from the formulators during the recent few years. Because co-crystals can enhance the physiochemical properties of pharmaceuticals without affecting their therapeutic effect, the area of pharmaceutical co-crystals has reached a tipping point. Besides increasing solubility, some more applications of co-crystals have also been identified to enhance physicochemical properties like permeability, bioavailability, stability, tablet ability, etc. Co-crystals have been extensively studied in the literature, and there is a tremendous amount of literature on co-crystals. However, an exhaustive review of coformer selection and co-crystal regulation must be included. An effort has been made in the review to fill this void. The current study focuses on how co-crystallization can enhance the pharmaceutical characteristics of different drugs, besides giving an overview of the historical background and landmarks in discovering co-crystals. In this review paper, we have discussed the rational design of co-crystals and the selection of conformers for the synthesis of multi-component co-crystals, methods like H-bonding, PKa value, Synthonic engineering, Cambridge structural database, Hansen solubility parameter (HSP), etc as well as the IPR related details all across the world. There is an attempt to include reported works on co-crystals, which helps understand the concept. This review paper discusses pharmaceutical regulatory bodies in the US and Europe released guidelines that are highly useful for pharmaceutical product registration in these regions. Here, we also examine various commercially available pharmaceutical drug products. It also briefly predicts the future perspective of co-crystallization. Crystallization ; Solubility ; Crystal engineering ; Active ingredient ; Materials science ; Crystal (programming language) ; Rational design ; Bioavailability ; Stoichiometry ; Chemical engineering ; Nanotechnology ; Biochemical engineering ; Combinatorial chemistry ; Chemistry ; Computer science ; Hydrogen bond ; Organic chemistry ; Molecule ; Bioinformatics Crystallization and Solubility Studies ; Crystallography and molecular interactions ; Enzyme Structure and Function
Authors: Yuming Wen | Jianfeng Zheng | Alex H. Evans | Qiang Zhang
Source: Organics (article, 2023-06-13)
Field: Chemistry — Organic Chemistry

Palladium Catalyzed Allylic C-H Oxidation Enabled by Bicyclic Sulfoxide Ligands The activation of C-H bonds is a potent tool for modifying molecular structures in chemistry. This article details the steps involved in a novel ligand bearing a bicyclic [3.3.1]-nonane framework and bissulfoxide moiety. A palladium catalyzed allylic C-H oxidation method enables a direct benzyl-allylic functionalization with the bissulfoxide ligand. Bissulfoixde ligand possesses a rapidly constructed bicyclic [3.3.1] framework and it proved to be effective for enabling both N-and C-alkylation. A total of 13 C-H activation productions were reported with good to excellent yields. This report validated that it is necessary to include bissulfoxide as a ligand for superior reactivities. Naftifine was produced utilizing developed C-H functionalization methodology in good overall yields. Bicyclic molecule ; Ligand (biochemistry) ; Palladium ; Allylic rearrangement ; Moiety ; Chemistry ; Tsuji–Trost reaction ; Combinatorial chemistry ; Sulfoxide ; Catalysis ; Surface modification ; Stereochemistry ; Organic chemistry Catalytic C–H Functionalization Methods ; Synthesis and Catalytic Reactions ; Oxidative Organic Chemistry Reactions
Authors: Emma Danelius | Guojun Bu | Hermina Wieske | Tamir Gonen
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2023-08-01)
Field: Chemistry — Spectroscopy

MicroED as a powerful tool for structure determination of macrocyclic drug compounds directly from their powder formulations Macrocycles are important drug leads with many advantages including the ability to target flat and featureless binding sites as well as act as molecular chameleons and thereby reach intracellular targets. However, due to their complex structures and inherent flexibility, macrocycles are difficult to study structurally and there are limited structural data available. Herein, we use the cryo-EM method MicroED to determine the novel atomic structures of several macrocycles which have previously resisted structural determination. We show that structures of similar complexity can now be obtained rapidly from nanograms of material, and that different conformations of flexible compounds can be derived from the same experiment. These results will have impact on contemporary drug discovery as well as natural product exploration. Combinatorial chemistry ; Drug ; Chemistry ; Chromatography ; Nanotechnology ; Materials science ; Medicine ; Pharmacology Analytical Chemistry and Chromatography ; Mass Spectrometry Techniques and Applications ; Analytical chemistry methods development
Authors: Loris Laze | Beatriz Quevedo-Flores | Irene Bosque | José C. González‐Gómez
Source: ChemRxiv (preprint, 2023-08-01)
Field: Chemistry — Organic Chemistry

Metal- and chlorine-free cross-dehydrogenative coupling of azaarenes with alkanes without sacrificial oxidants. Minisci-like cross-dehydrogenative coupling of azaarenes with unactivated alkanes offers an appealing approach to bioactive alkyl-substituted heterocycles from abundant feedstocks. Traditionally, this net oxidative C-C bond formation process uses sacrificial chemical oxidants with the consequent waste generation. Here we report a chemical oxidant-free solution for this transformation, promoted by visible light at room temperature in the absence of metals and chlorinated solvents. The reaction relies on the interplay of a readily available 9-arylacridine and inexpensive pyridine N-oxide as pre-catalysts. A wide range of azaarenes and C(sp3)-H partners are compatible with this protocol, which was applied to the late-stage functionalization of bioactive molecules and the gram-scale synthesis of one API intermediate using flow technology. Preliminary mechanistic studies support the dual catalytic cycle with H2 evolution. Catalysis ; Chemistry ; Alkyl ; Pyridine ; Combinatorial chemistry ; Chlorine ; Organic chemistry Catalytic C–H Functionalization Methods ; Asymmetric Hydrogenation and Catalysis ; Synthesis and Catalytic Reactions
Authors: Man Zhu | Ming Ke | Wenjing Zhao | Qingqing Wu | Shaoguang Li | Hui Li | Fan Xia
Source: Analysis & Sensing (article, 2023-08-23)
Field: Chemistry — Inorganic Chemistry

Application of Metal‐Organic Frameworks in Imaging‐Guided Therapy Abstract Metal‐organic frameworks (MOFs) are formed by the self‐assembly of metal centres/clusters and organic ligands. A diverse range of organic ligands can be employed, including nucleobases, amino acids, peptides, proteins, and saccharides et al . Due to the characteristics of large surface area, high porosity, easy surface functionalization and adjustable internal pore size, et al . MOFs have been used as a significant emerging class of biological imaging agents and have attracted great research interest in optical imaging (OI), photoacoustic imaging (PAI), magnetic resonance imaging (MRI), computer tomography (CT) and positron emission tomography (PET) in recent years. This review provides a comprehensive overview of the diverse range of organic ligands utilized in Metal‐organic frameworks, while also delving into the recent advancements, opportunities, and challenges encountered in the realm of bioimaging in recent years. Metal-organic framework ; Surface modification ; Nanotechnology ; Materials science ; Photoacoustic imaging in biomedicine ; Positron emission tomography ; Magnetic resonance imaging ; Porosity ; Chemistry ; Medicine ; Organic chemistry ; Nuclear medicine ; Radiology ; Physics ; Optics ; Physical chemistry Metal-Organic Frameworks: Synthesis and Applications ; Nanoplatforms for cancer theranostics ; Advanced Nanomaterials in Catalysis
Authors: Mahboubeh Jamshidi | Joey Bouheriche | James M. Gardner
Source: Frontiers in Chemistry (article, 2023-12-11)
Field: Materials Science — Materials Chemistry

Photoluminescent copper(I) iodide alkylpyridine thin films as sensors for volatile halogenated compounds The paper presents the fabrication and characterization of [CuI(L)]<sub>n</sub> thin films, where L represents various alkylpyridine ligands including 4-methylpyridine, 3-methylpyridine, 2-methylpyridine, 4-<sup>t</sup>butylpyridine, 3,4-dimethylpyridine, and 3,5-dimethylpyridine. The thin films were synthesized by exposing the corresponding ligands to CuI thin films through vapor deposition. The coordination reactions occurring on the films were investigated using PXRD and time-dependent photoluminescence spectroscopy, and a comparison was made between the structures of the thin films and the corresponding powder phases. The films showed primarly blue emission (λ<sub>em</sub> = 457-515 nm) and polymeric structures with excited state lifetimes ranging from 0.6 to 5.5 μs. Significantly, the studied compounds exhibited fast reversible luminescence quenching when exposed to vapors of dichloromethane and dibromomethane (15 and 30 min respectively), and the luminescence was restored upon re-exposure to the alkylpyridine ligand (after 20 min). These findings indicate that these thin films hold promise for applications as sensors (with sensitive and reversible detection capability) for volatile halogen-based compounds (VHC). Thin film ; Photoluminescence ; Luminescence ; Halogen ; Dichloromethane ; Iodide ; Materials science ; Quenching (fluorescence) ; Analytical Chemistry (journal) ; Copper ; Photochemistry ; Chemistry ; Fluorescence ; Inorganic chemistry ; Nanotechnology ; Organic chemistry ; Optoelectronics ; Optics ; Solvent Copper-based nanomaterials and applications ; Nanocluster Synthesis and Applications ; Nanomaterials for catalytic reactions
Authors: Emma G. L. Robert | Vincent Pirenne | Matthew D. Wodrich | Jérôme Waser
Source: Angewandte Chemie (article, 2023-04-19)
Field: Chemistry — Organic Chemistry

Donor‐Acceptor Aminocyclobutane Monoesters: Synthesis and Silylium‐Catalyzed (4+2) Annulation with Indoles Abstract A convenient one‐step synthesis of β‐aminocyclobutane monoesters starting from commercially available reagents is reported. The obtained strained rings undergo (4+2) dearomative annulation with indole partners using silylium catalysis. This organocatalyzed annulation provided tricyclic indolines with four new stereocenters in up to quantitative yield and &gt;95 : 5 diastereoselectivity and can proceed both intra‐ and intermolecularly. When performed intramolecularly, the tetracyclic structure of either akuamma or malagasy alkaloids was obtained selectively depending on the temperature of the reaction. This divergent outcome could be rationalized based on DFT calculations. Annulation ; Stereocenter ; Chemistry ; Indole test ; Reagent ; Catalysis ; Yield (engineering) ; Combinatorial chemistry ; Acceptor ; Stereochemistry ; Organic chemistry ; Enantioselective synthesis ; Materials science Cyclopropane Reaction Mechanisms ; Catalytic C–H Functionalization Methods ; Asymmetric Synthesis and Catalysis
Authors: Jorge Tavares | Cátia Venâncio | Cláudia Margarida Gouveia Duarte | Filipe E. Antunes | Isabel Lopes
Source: Environmental Science and Pollution Research (article, 2023-01-04)
Field: Chemistry — Organic Chemistry

Adding knowledge to the design of safer hydrophobically modified poly(acrylic) acids: an ecotoxicological approach Daphnia magna ; Ecotoxicity ; Biology ; Population ; Food science ; Chemistry ; Toxicology ; Organic chemistry ; Toxicity Antimicrobial agents and applications ; Pesticide and Herbicide Environmental Studies ; biodegradable polymer synthesis and properties
Authors: Barham K. Rahim | Peshawa O. Amin | Fahmi F. Muhammadsharif | Salah Raza Saeed | Kamal Aziz Ketuly
Source: ARO-The Scientific Journal of Koya University (article, 2023-04-17)
Field: Materials Science — Polymers and Plastics

Optical and Optoelectronic Studies of Binary and Ternary Films of Poly(L-Tryptophane), Poly(5-hydroxy-L-tryptophane), and P(TER-CO-TRI) Doped with Sudan Dye In this work, the optical properties and optoelectronics parameters of binary and ternary composite films made of two electron acceptors, poly(L-Tryptophane) and poly(5-hydroxy-L-Tryptophane), with an electron donor, P(TER-CO-TRI), doped with Sudan dyes, are comprehensively investigated. The films with different volumetric ratios of the components were deposited onto the glass substrates using spin coating technique. Results showed that with the help of dye doping into the binary systems of poly(L-Tryptophane):P(TRI-co-TER) (1:2) and poly(5-hydroxy-L-Tryptophane):P(TRI-co-TER)(1:2), the refractive index was increased from 2.01 to 2.32. The nature of the electronic transition in the studied films was found to be a direct allowed transition, which was derived from Tauc’s equation. The combination of Cyclic voltammetry (CV) technique and absorption spectroscopy was used to determine the molecular energy levels, HOMO and LUMO of the polymer samples. It was seen that the mixture of poly(L-Tryptophane):P(TRI-co-TER):Sudan dye (1:2:2) has led to increase the energy gap to 2.95 eV and the real optical conductivity ( ) to about 433.11 S.cm-1. According to the findings, the investigated polymers can have a great potential for semitransparent organic solar cells. Ternary operation ; Materials science ; HOMO/LUMO ; Cyclic voltammetry ; Spin coating ; Doping ; Glass transition ; Band gap ; Polymer ; Absorption (acoustics) ; Analytical Chemistry (journal) ; Absorption spectroscopy ; Optical conductivity ; Physical chemistry ; Chemistry ; Thin film ; Molecule ; Organic chemistry ; Optics ; Nanotechnology ; Optoelectronics ; Electrochemistry ; Electrode Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Polymer Nanocomposite Synthesis and Irradiation
Authors: R. Pérez | Jerónimo Agrisuelas | Alicia Gomis‐Berenguer | M. T. Baeza‐Romero | Edelmira Valero
Source: Electrochimica Acta (article, 2023-05-31)
Field: Materials Science — Polymers and Plastics

One-pot electrodeposition of multilayered 3D PtNi/polymer nanocomposite. H2O2 determination in aerosol phase In this work, 3D-structured nanocomposites were synthesized in one pot by electrochemical deposition of alternating layers of an azo type polymer (polyazure-A) with platinum and nickel nanoparticles. The hybrid PtNi/poly(AzA) film was electrochemically deposited on screen-printed carbon electrodes by layer-by-layer assembly as a function of the number of cyclic voltammograms for electrodeposition of the conducting polymer and the electrode potential applied for electro-reduction of the metal salts. The physicochemical characteristics of the resulting films were studied using electrochemical and microscopic techniques. The 3D molecular nanoarchitecture presents a hollow porous structure dependent on the electrode potential set for the electro-reduction of Pt and Ni nanoparticles. The electrochemical sensor was validated in terms of sensitivity, limit of detection, stability and repeatability, exhibiting a highly sensitive H2O2 detection, with LoD 68.5 nM (S/N = 3) at 0.05 V vs. Ag-SPCE for the electrode modified with 20 cycles for the conducting polymer electrodeposition and −2.0 V for metal ions reduction. The aim of this work also included the outcome of the electrochemical sensor after incorporating the room temperature ionic liquid 1‑butyl‑2,3-dimethylimidazolium tetrafluoroborate within the PtNi/poly(AzA) film, which notably improved the analytical parameters of the system, with LoD 14.5 nM at the same potential. Therefore, as proof of concept, the PtNi/poly(AzA) film-based electrode was explored towards the suitability of an electrochemical sensor for the determination of hydrogen peroxide in aerosol phase. The outstanding features of the PtNi/poly(AzA) film-based electrode modified with the aforementioned ionic liquid allowed for the continuous monitoring of H2O2 in an aerosol stream generated with an ultrasonic diffuser at the low applied potential of 0.05 V. In addition, monitoring H2O2 samples through a series of ON/OFF switches for over 3 h, the sensor provided a fast and reproducible response. Materials science ; Electrochemistry ; Electrode ; Nanocomposite ; Chemical engineering ; Polymer ; Nanoparticle ; Electrochemical gas sensor ; Ionic liquid ; Nanotechnology ; Chemistry ; Composite material ; Organic chemistry ; Physical chemistry Conducting polymers and applications ; Electrochemical sensors and biosensors ; Electrochemical Analysis and Applications
Authors: Nemanja Gavrilov | Stefan Breitenbach | Christoph Unterweger | Christian Fürst | Igor A. Pašti
Source: C – Journal of Carbon Research (article, 2023-11-06)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Exploring the Impact of DAHP Impregnation on Activated Carbon Fibers for Efficient Charge Storage and Selective O2 Reduction to Peroxide Understanding the properties and behavior of carbon materials is of paramount importance in the pursuit of sustainable energy solutions and technological advancements. As versatile and abundant resources, carbon materials play a central role in various energy conversion and storage applications, making them essential components in the transition toward a greener and more efficient future. This study explores the impact of diammonium hydrogen phosphate (DAHP) impregnation on activated carbon fibers (ACFs) for efficient energy storage and conversion applications. The viscose fibers were impregnated with varying DAHP concentrations, followed by carbonization and activation processes. The capacitance measurements were conducted in 6 mol dm−3 KOH, 0.5 mol dm−3 H2SO4, and 2 mol dm−3 KNO3 solutions, while the oxygen reduction reaction (ORR) measurements were performed in O2-saturated 0.1 mol dm−3 KOH solution. We find that the presented materials display specific capacitances up to 160 F g−1 when the DAHP concentration is in the range of 1.0 to 2.5%. Moreover, for the samples with lower DAHP concentrations, highly selective O2 reduction to peroxide was achieved while maintaining low ORR onset potentials. Thus, by impregnating viscose fibers with DAHP, it is possible to tune their electrochemical properties while increasing the yield, enabling the more sustainable and energy-efficient synthesis of advanced materials for energy conversion applications. Viscose ; Hydrogen peroxide ; Activated carbon ; Carbonization ; Supercapacitor ; Energy storage ; Chemical engineering ; Materials science ; Carbon fibers ; Chemistry ; Electrochemistry ; Nanotechnology ; Organic chemistry ; Electrode ; Composite material ; Adsorption Supercapacitor Materials and Fabrication ; Advanced Battery Materials and Technologies ; Conducting polymers and applications
Authors: Florent Pawula | Solène Perrot | Georges Hadziioannou | Guillaume Fleury
Source: Organic Electronics (article, 2023-03-23)
Field: Materials Science — Materials Chemistry

Nanotextured PEDOT:Tos layers from block copolymer lithography PEDOT:PSS ; Materials science ; Nanotechnology ; Conductive polymer ; Lithography ; Doping ; Polymer ; Electronics ; Organic electronics ; Optoelectronics ; Layer (electronics) ; Transistor ; Composite material ; Chemistry Block Copolymer Self-Assembly ; Organic Electronics and Photovoltaics ; Conducting polymers and applications
Authors: Laise Maia Lopes | Mariana Agostini de Moraes | Marisa Masumi Beppu
Source: Advances in Polymer Technology (article, 2023-11-28)
Field: Materials Science — Biomaterials

Influence of Guluronic and Mannuronic Groups in Sodium Alginate Blends with Silk Fibroin: Phase Equilibrium and Thermodynamic Modeling Silk fibroin (SF) and sodium alginate (SA) are natural polymers with interesting properties to produce biomaterials. Blends of these polymers form a complex protein–polysaccharide system where phase separation can be observed. Therefore, the thermodynamic analysis of this system is important to understand the interaction between the polymers and predict the final state and composition of the phases found in these blends. This study explored blends with a different initial composition of SF, SA, and water at 25°C and neutral pH. The influence of the proportion between mannuronic and guluronic acids on SA composition was investigated. After phase separation, two phases were identified, and the equilibrium data were fitted on three different thermodynamic models: Flory–Huggins, non-random two-liquids, and universal quasichemical. Cohn equation was also used to investigate the potential of SA to precipitate the SF in solution. The results show that the proportion of mannuronic and guluronic acids on the SA can significantly influence on equilibrium data and on the SF/SA interaction parameter, hence, becoming a variability factor if this parameter is not under control in formulations. Fibroin ; Polymer ; Materials science ; Thermodynamics ; Phase (matter) ; Polymer blend ; Flory–Huggins solution theory ; Chemical engineering ; SILK ; Chemistry ; Organic chemistry ; Composite material ; Physics Silk-based biomaterials and applications ; Polymer Surface Interaction Studies ; Collagen: Extraction and Characterization