jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Jaeseong Jin | Su‐min Song | Jun‐Ho Choi | Won‐jin Chung
Source: Science Advances (article, 2024-10-30)
Field: Chemistry — Organic Chemistry

Stereoselective synthesis of geminal bromofluoroalkenes by kinetically controlled selective conversion of oxaphosphetane intermediates Geminal bromofluoroalkenes are an important subclass of versatile organic interhalide, which can serve as useful synthetic precursors to monofluoroalkenes that are valuable amide group isosteres. Nonetheless, despite the vast advancement of olefination methodologies, the broadly applicable stereoselective synthesis remained elusive for geminal bromofluoroalkenes before our work. In particular, the seemingly straightforward Wittig-type approach with interhalogenated phosphorus ylide has been unsuccessful because of the difficulty in the diastereoselective oxaphosphetane formation. Here, we describe a conceptually distinctive strategy, by which the stereoselectivity is gained via the selective decomposition of the oxaphosphetane intermediates. The suitably identified phosphorus(III) reagent and reaction medium enabled efficient kinetic differentiation, which was supported by nuclear magnetic resonance analysis and density functional theory calculation. Through our method, the highly diastereoselective synthesis of geminal <i>E</i>-bromofluoroalkenes was accomplished in one step. Furthermore, the generality was demonstrated by accommodating a wide range of readily available carbonyl compounds, including ketones and pharmaceutical substrates. Geminal ; Stereoselectivity ; Ylide ; Chemistry ; Amide ; Combinatorial chemistry ; Organic synthesis ; Wittig reaction ; Reagent ; Functional group ; Organic chemistry ; Computational chemistry ; Catalysis Phosphorus compounds and reactions ; Advanced Synthetic Organic Chemistry ; Organophosphorus compounds synthesis
Authors: J Pavan Kumar | Chennu MM Prasada Rao | Ranjan Kumar Singh | Ajay Garg | Tanniru Rajeswari
Source: Journal of Drug Delivery and Therapeutics (article, 2024-08-15)
Field: Materials Science — Biomaterials

A Comprehensive Guide to Hydrogel-Based Controlled Drug Delivery for Cancer Treatment Common kinds of chemotherapy may cause harm to normal cells and tissues. Localised chemotherapy, unlike systemic chemotherapy, can lessen side effects by providing a consistent supply of chemotherapeutic chemicals directly to the tumour location. This emphasises the importance of controlled-release biodegradable hydrogels as chemotherapeutic drug delivery systems. This study looks at employing hydrogels as drug delivery methods for HCC, including thermosensitive, pH-sensitive, photosensitive, dual-sensitive, and glutathione-responsive hydrogels. Hydrogel-based drug delivery systems outperform traditional systemic chemotherapy in cancer treatment. Cancer immunotherapy has emerged as the new paradigm for cancer treatment. The development and discovery of new therapeutic molecules has increased the use of immunotherapy in clinical studies. This article discusses the current state of functional hydrogels for effective cancer immunotherapy. First, we will discuss the fundamental principles of cancer immunotherapy and the benefits of employing hydrogels to implement these mechanisms. Finally, we briefly explore the existing issues and potential applications of hydrogels for effective cancer immunotherapy. Keywords: Cancer, Hydrogel-based controlled drug delivery system, postoperative radiotherapy, chemotherapy, Immunotherapy. Drug delivery ; Drug ; Medicine ; Pharmacology ; Nanotechnology ; Materials science Nanoparticle-Based Drug Delivery ; Graphene and Nanomaterials Applications ; Hydrogels: synthesis, properties, applications
Authors: Kishor More | Anil Rakshe | Sudam Chavhan | S. J. Nandre | R.R. Ahire | Anup More
Source: ES Materials & Manufacturing (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Effect of Precursor Salt Variation on Structural, Morphological and Optoelectronic Properties of Zinc Oxide Thin Films Deposited via Sol-gel Spin Coating Spin coating ; Sol-gel ; Zinc ; Thin film ; Salt (chemistry) ; Materials science ; Chemical engineering ; Coating ; Oxide ; Nanotechnology ; Chemistry ; Metallurgy ; Organic chemistry ZnO doping and properties ; Copper-based nanomaterials and applications ; Gas Sensing Nanomaterials and Sensors
Authors: Varad Agarwal | Ambreen Nisar | Abhijith Kunneparambil Sukumaran | Lihua Lou | Sohail M.A.K. Mohammed
Source: Lubricants (article, 2024-01-24)
Field: Materials Science — Materials Chemistry

Synergistic Effect of Spark Plasma Sintering Driven Solid-Solution Phases on Scratch Resistance in Two-Dimensional Materials Developing a solid lubricant with the ideal blend of lubrication and mechanical strength poses a formidable challenge. For the first time, we delve into synthesis and wear behavior of multicomponent 2D materials via spark plasma sintering (SPS) by mixing equimolar concentrations of hexagonal boron nitride (hBN), graphene nanoplatelets (GNPs), molybdenum disulfide (MoS2), and tungsten disulfide (WS2) using ball-milling (BM) and cryo-milling (CM) techniques. The mixing process controls the distribution of parent phases and thus solid-solutions, forming new phases, namely BCN, (Mo,W)S2, and B4C in the sample post sintering. The CM sample revealed a higher densification of 93% in contrast to the BM sample, with only 86% densification and a higher content of BCN, (Mo,W)S2, and B4C phases, exhibited via XRD and confocal Raman analysis. CM sample showed improved wear resistance (up to 46%) elicited from the lower wear volume loss (9.78 × 106 µm3) as compared to the BM sample (14.32 × 106 µm3). The dominant wear mechanisms were plowing, cracking, spallation, and severe abrasion in the BM sample, while cracking and plowing in the CM sample. The findings can pave the way for tailoring solid lubricants’ compositions and wear behavior per the intended application. Spark plasma sintering ; Scratch ; Materials science ; Plasma ; Sintering ; SPARK (programming language) ; Chemical engineering ; Metallurgy ; Composite material ; Computer science Diamond and Carbon-based Materials Research ; MXene and MAX Phase Materials ; Graphene research and applications
Authors: Liqun Ye | Xiaorong Gan | Romana Schirhagl
Source: Preprints.org (preprint, 2024-11-19)
Field: Materials Science — Materials Chemistry

Two-Dimensional MoS2-Based Photodetectors Nanomaterials used can significantly improve the analytical performance of optical sensors to environmental pollutants. Two-dimensional (2D) molybdenum sulfide (MoS2) exhibits some unique physicochemical properties such as strong light-matter interaction, bandgap tunability, and high carrier mobility, which are beneficial for constructing flexible optoelectronic devices. In this Review, the principle and classification of 2D MoS2-based photodetectors (PDs) are introduced, followed by a discussion about the physicochemical properties of 2D MoS2, as well as structure-property relationships of 2D MoS2-based photoactive materials for PDs to understand the modulation strategies for enhancing the photodetection performance. Furthermore, we discuss significant advances in the surface modification and functionalization of 2D MoS2 for developing high-performance PDs, particularly focusing on synthesis pathways, modification strategies, and underlying physiochemical mechanisms for enhanced photodetection capabilities. Finally, conclusions and research perspectives on resolving significant bottlenecks or remaining challenges are offered based on recent developments in 2D MoS2-based PDs. Photodetection ; Photodetector ; Materials science ; Surface modification ; Nanomaterials ; Optoelectronics ; Molybdenum disulfide ; Nanotechnology ; Band gap ; Modulation (music) ; Computer science ; Physics ; Chemistry 2D Materials and Applications ; Gas Sensing Nanomaterials and Sensors ; Advanced Photocatalysis Techniques
Authors: Xiaoyu Hao | Huixia Yang | Mengmeng Niu | Tingting Wang | Hongyan Ji | Iulia Emilia Brumboiu | Cesare Grazioli | Ambra Guarnaccio | Albano Cossaro | Yan Li | Jingsi Qiao | Quanzhen Zhang | Liwei Liu | Teng Zhang | Yeliang Wang
Source: Nanomaterials (article, 2024-12-05)
Field: Chemistry — Organic Chemistry

From Chains to Arrays: Substrate-Mediated Self-Assembly of Diboron Molecules In this study, we explore the substrate-mediated control of self-assembly behavior in diboron molecules (C<sub>12</sub>H<sub>8</sub>B<sub>2</sub>O<sub>4</sub>, B<sub>2</sub>Cat<sub>2</sub>) using scanning tunneling microscopy (STM). The structural transformation of B<sub>2</sub>Cat<sub>2</sub> molecules from one-dimensional (1D) molecular chains to two-dimensional (2D) molecular arrays was achieved by changing the substrate from Au(111) to bilayer graphene (BLG), highlighting the key role of substrate interactions in determining the assembly structure. Notably, the B-B bond in the molecular arrays on BLG is distinctly pronounced, reflecting a more refined molecular resolution with distinct electronic states than that on Au(111). Density functional theory (DFT) calculations confirm the weak interaction between B<sub>2</sub>Cat<sub>2</sub> molecules and the BLG substrate, which facilitates the formation of 2D molecular arrays on BLG. This work demonstrates how controlling substrate properties enables the formation of 1D chains and 2D arrays, providing valuable insights for the design of next-generation molecular electronics and catalysis systems. Substrate (aquarium) ; Molecule ; Chemistry ; Stereochemistry ; Materials science ; Nanotechnology ; Combinatorial chemistry ; Organic chemistry ; Biology Organoboron and organosilicon chemistry ; Molecular Junctions and Nanostructures ; Luminescence and Fluorescent Materials
Authors: Pralay Maiti
Source: Biomedical Journal of Scientific & Technical Research (article, 2024-07-17)
Field: Materials Science — Biomaterials

Battle Against Drug Resistant Cancer Using Nanotechnology: Cellular and Molecular Mechanistic Pathways Cancer, with its somber embrace, stands as one of the foremost reasons of mortality across the globe.Chemotherapy stands as the steadfast cornerstone in the battle against cancer.Yet, amidst its promise, a formidable obstacle casts its shadow, impeding the triumph of this therapeutic endeavor is its multidrug resistance.In the intricate realm of medical advancement, nanotechnology emerges as a luminary, its delicate intricacies and infinitesimal wonders offering profound promise in the fight against cancer.Against the backdrop of conventional pharmaceuticals, they unveil a unique advantage with greater precision and purpose.Enhanced stability and biocompatibility grace their essence, while an inherent ability to navigate the labyrinthine pathways of the body while enhances their efficacy.Moreover, in the chronicles of resistance and resilience, nanoparticlebased drug delivery systems emerge as champions, wielding their prowess against the scourge of drug resistance in cancer.Multi-drug resistance stems from various unrelated mechanisms, including overexpression of proteins, reduced drug uptake, altered drug targets, cell cycle checkpoint modifications, agent inactivation, compartmentalization, apoptosis inhibition, and abnormal sphingolipid metabolism.Nanoparticles targeting drug resistance mechanisms can enhance reversal of multidrug resistance.Additionally, as extra resistance mechanism emerges where nanoparticles are progressively utilized to target them.Researchers are exploring nanoparticles' role in immunotherapy, crucial in cancer treatment.This review examines nanoparticles' roles, including hybrid nanoparticles, in delivery of drug for immunotherapy, chemotherapy and targeted therapy, highlighting their targeting mechanisms and ability to reverse drug resistance along with cellular and molecular mechanism (Graphical Abstract). Battle ; Nanotechnology ; Drug ; Cancer ; Cancer drugs ; Computational biology ; Chemistry ; Biology ; Materials science ; Pharmacology ; Geography ; Genetics Nanoparticle-Based Drug Delivery ; Nanoplatforms for cancer theranostics ; Cancer Research and Treatment
Authors: Vladyslav Polishchuk | Andrii V. Kulinich | Mykola P. Shandura
Source: Chemistry - A European Journal (article, 2024-04-16)
Field: Materials Science — Materials Chemistry

Tetraanionic Oligo‐Dioxaborines: Strongly Absorbing Near‐Infrared Dyes Polymethine dyes of tetraanionic nature comprising 1,3,2-dioxaborine rings in the polymethine chain and end-groups of different electron-accepting abilities have been synthesized. They can be considered as oligomeric polymethines, where a linear conjugated π-system passes through three 1,3,2-dioxaborine units and a number of tri- and dimethine π-bridges between two end-groups. The obtained dyes exhibit near-infrared absorption and fluorescence, with molar absorption coefficients reaching as high as 564000 M<sup>-1</sup> cm<sup>-1</sup> in DMF, rendering them among the strongest absorbers known. The novel compounds are bright NIR fluorophores, with fluorescence quantum yields up to 0.13 in DMF. A comparative analysis of the electronic structure of the obtained dyes with respective dianionic and trianionic oligomers was conducted through quantum chemical calculations. Conjugated system ; Fluorescence ; Chemistry ; Quantum chemical ; Photochemistry ; Absorption (acoustics) ; Infrared ; Rendering (computer graphics) ; Materials science ; Molecule ; Organic chemistry ; Polymer ; Optics ; Physics Luminescence and Fluorescent Materials ; Conducting polymers and applications ; Synthesis and Properties of Aromatic Compounds
Authors: Hussein I. Mahdi | Nabeel A. Bakr | Tagreed M. Al‐Saadi
Source: Iraqi Journal of Science (article, 2024-08-30)
Field: Materials Science — Materials Chemistry

Studying the Gas Sensitivity and Magnetic Properties of Magnesium Ferrite Prepared by the Sol-Gel Route Nickel-doped manganese–magnesium ferrite (NixMn0.25-xMg0.75Fe2O4) was prepared using the auto-combustion method. X-ray diffraction patterns showed a single ferrite spinel phase in all the prepared samples. The crystallite size ranged from 24.30 to 28.32 nm, increasing with increasing the Ni content. The porous structure of all the samples was verified with a scanning electron microscope. FE-SEM images were used to confirm the production of spherical or semi-spherical nanoparticles with little change in particle size distribution. The study revealed that the nanoparticles were small enough to behave superparamagnetically. According to the magnetic tests conducted with the VSM at room temperature, the hysteresis loop region is practically non-existent, indicating typical soft magnetic materials. In addition, the conductance responses of the magnesium ferrite nanocomposite were measured by exposing it to the oxidizing gas (NO2) at different operating temperatures. The results showed that the sensor with the nano ferrite sample of (x = 0.20) has a good sensitivity of 707.22% as well as response and recovery times. Magnesium ; Sensitivity (control systems) ; Ferrite (magnet) ; Materials science ; Sol-gel ; Chemical engineering ; Metallurgy ; Composite material ; Nanotechnology ; Engineering Magnetic Properties and Synthesis of Ferrites
Authors: Patrícia Dias | Rudy Salam | Jana Pourová | Marie Vopršalová | Lukáš Konečný | Eduard Jirkovský | Jurjen Duintjer Tebbens | Přemysl Mladěnka
Source: Food & Function (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

The quercetin metabolite 4-methylcatechol causes vasodilation <i>via</i> voltage-gated potassium (K<sub>V</sub>) channels Dietary polyphenols have been associated with many beneficial cardiovascular effects. However, these effects are rather attributed to small phenolic metabolites formed by the gut microbiota, which reach sufficient concentrations in systemic circulation. 4-Methylcatechol (4-MC) is one such metabolite. As it is shown to possess considerable vasorelaxant effects, this study aimed to unravel its mechanism of action. To this end, experimental <i>in vitro</i> and <i>in silico</i> approaches were employed. In the first step, isometric tension recordings were performed on rat aortic rings. 4-MC potentiated the effect of cyclic nucleotides, but the effect was not mediated by either soluble guanylyl cyclase (sGC), modification of cyclic adenosine monophosphate levels, or protein kinase G. Hence, downstream targets such as calcium or potassium channels were considered. Inhibition of voltage-gated K<sup>+</sup> channels (K<sub>V</sub>) markedly decreased the effect of 4-MC, and vasodilation was partly decreased by inhibition of the K<sub>V</sub>7 isoform. Contrarily, other types of K<sup>+</sup> channels or L-type Ca<sup>2+</sup> channels were not involved. <i>In silico</i> reverse docking confirmed that 4-MC binds to K<sub>V</sub>7.4 through hydrogen bonding and hydrophobic interactions. In particular, it interacts with two crucial residues for K<sub>V</sub>7.4 activation: Trp242 and Phe246. In summary, our findings suggested that 4-MC exerts vasorelaxation by opening K<sub>V</sub> channels with the involvement of K<sub>V</sub>7.4. Potassium channel ; ATP-sensitive potassium channel ; Metabolite ; Chemistry ; Quercetin ; Vasodilation ; Potassium ; Voltage-gated potassium channel ; Pharmacology ; Biophysics ; Medicine ; Biology ; Biochemistry ; Internal medicine ; Endocrinology Free Radicals and Antioxidants ; Receptor Mechanisms and Signaling ; Ion channel regulation and function
Authors: Yan Jiang | Haojie Ma | Chen-Ying Zhai | Xuelong Wang | Yi Yang
Source: Asian Journal of Organic Chemistry (article, 2024-12-12)
Field: Chemistry — Organic Chemistry

Sc(OTf)<sub>3</sub>‐Catalyzed Tunable Thio‐(3+3) Annulation Reactions of Indoline‐2‐thiones with α‐Benzylidene‐β‐tetralones Abstract A Sc(OTf) 3 ‐catalyzed tunable thio‐Michael addition/nucleophilic addition/dehydration reaction of indoline‐2‐thiones with α‐benzylidene‐β‐tetralones was realized, leading to biologically important tetrahydrobenzo[7,8]isothiochromeno[3,4‐b]indoles and thiazino[3,2‐a]indoles in moderate to good yields. Moreover, by extending the reaction time, the dehydrogenated cycloadducts dihydrobenzo[7,8]isothiochromeno[3,4‐b]indoles were also obtained from the reaction of indoline‐2‐thiones with α‐benzylidene‐β‐tetralones. Indoline ; Chemistry ; Thio- ; Tetralones ; Annulation ; Dehydrogenation ; Catalysis ; Medicinal chemistry ; Indole test ; Organic chemistry Sulfur-Based Synthesis Techniques ; Synthesis and Catalytic Reactions ; Synthesis of Indole Derivatives
Authors: Saki Arimura | Ikuya Matsumoto | Ryo Sekiya | Takeharu Haino
Source: Angewandte Chemie (article, 2024-01-06)
Field: Materials Science — Materials Chemistry

Intermediate Color Emission via Nanographenes with Organic Fluorophores Abstract Photoluminescence (PL) color can be tuned by mixing fluorophores emitting the three primary colors in an appropriate ratio. When color tuning is achieved on a single substrate, we can simplify device structures. We demonstrated that nanographenes (NGs), which are graphene fragments with a size of tens of nanometers, could be utilized as carriers of fluorophores. The addition of red‐ and blue‐light‐emitting fluorophores on the edge successfully reproduced the purple light. The relative PL intensities of the fluorophores could be regulated by the excitation wavelength, enabling multicolor emission between blue and red light. Owing to the triphenylamine units of the fluorophores, the NGs showed PL enhancement due to aggregation. This characteristic was valuable for the fabrication of solid polymer materials. Specifically, the functionalized NGs can be dispersed into polyvinylidene difluoride. The resultant polymer films emitted red, blue, and purple color. Our study demonstrated the potential applicability of NGs for fluorophore carriers capable of reproducing intermediate colors of light. Fluorophore ; Photoluminescence ; Materials science ; Fluorescence ; Optoelectronics ; Triphenylamine ; Polymer ; Photochemistry ; Chemistry ; Optics Luminescence and Fluorescent Materials ; Carbon and Quantum Dots Applications ; Synthesis and Properties of Aromatic Compounds
Authors: Isidro Cruz-Cruz | Roberto I. Servín-Quintero | Luis Marcelo Lozano | Alan O. Sustaita
Source: Heliyon (article, 2024-10-01)
Field: Materials Science — Polymers and Plastics

In-plane electrical conductivity of PEDOT:PSS/Halloysite composite thin films PSS has found numerous applications in the field of advanced materials, especially in the development of organic electronics. Embedding nanoparticles into the polymer matrix has emerged as an effective strategy to modify the properties of PEDOT:PSS and develop advanced functional composites. Over the past decade, Halloysite nanotubes (HNT) have garnered significant interest and utility as nanofillers and/or templates due to their unique physical-chemical properties, small size, relatively low cost, and large availability. Interestingly, pairing PEDOT:PSS with non-conductive HNT has been demonstrated to enhance the charge transport properties of the composite film. Our discoveries show how the HNT can act as scaffolding for PEDOT:PSS by improving the local ordering of PEDOT chains and enabling the formation of conductive pathways. Consequently, the mechanism responsible for the observed changes in conductivity and the correlation between PEDOT:PSS and insulating nanofillers (HNT) could be different to that previously proposed. Hence, in this work it was observed that PEDOT:PSS/HNT composite films exhibited a non-linear conductivity dependence as a function of the HNT loading. From thermogravimetric analysis, infrared and UV-Vis-NIR spectroscopies, as well as impedance spectroscopy, a more complex interaction between the polymer chains and the nanotubes is revealed. Our study includes the modification of the interaction between the PEDOT chains and the nanofillers by using the secondary doping effect and functionalization of the nanotubes, which confirms our findings. These results represent a significant progress toward a deeper understanding of the emergence of a conductive polymer network on the nanofiller surface, leading to improvements in the electrical conductivity in the composite material. Halloysite ; PEDOT:PSS ; Composite number ; Materials science ; Conductivity ; Thin film ; Composite material ; Electrical resistivity and conductivity ; Nanotechnology ; Electrical engineering ; Polymer ; Engineering ; Physics Conducting polymers and applications ; Clay minerals and soil interactions ; Advanced Battery Materials and Technologies
Authors: Yanhong Deng | Yifei Wang | Zhesheng Chen | Bo Xu | Jinjiang Wang | Éric Cloutet | Xiaojiao Yuan | Hengyang Xiang
Source: New Journal of Chemistry (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Organic π-conjugated trimers as fluorescent molecules for colorful electroluminescence Organic π-conjugated trimers as fluorescent molecules with very low molecular weights ( M w = 294 ∼ 466) and broad spectral tuning from blue to red show tremendous potential for display, lighting, and bio-imaging applications. Chemistry ; Conjugated system ; Fluorescence ; Electroluminescence ; Molecule ; Photochemistry ; Organic chemistry ; Polymer ; Optics Luminescence and Fluorescent Materials ; Sulfur-Based Synthesis Techniques ; Conducting polymers and applications