jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Cassandra A. Dutcher | Michael P. Andreas | Tobias W. Giessen
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2024-04-26)
Field: Materials Science — Materials Chemistry

A two-component quasi-icosahedral protein nanocompartment with variable shell composition and irregular tiling Protein shells or capsids are a widespread form of compartmentalization in nature. Viruses use protein capsids to protect and transport their genomes while many cellular organisms use protein shells for varied metabolic purposes. These protein-based compartments often exhibit icosahedral symmetry and consist of a small number of structural components with defined roles. Encapsulins are a prevalent protein-based compartmentalization strategy in prokaryotes. All encapsulins studied thus far consist of a single shell protein that adopts the viral HK97-fold. Here, we report the characterization of a Family 2B two-component encapsulin from <i>Streptomyces lydicus</i>. We show the differential assembly behavior of the two shell components and demonstrate their ability to co-assemble into mixed shells with variable shell composition. We determined the structures of both shell proteins using cryo-electron microscopy. Using 3D-classification and crosslinking studies, we highlight the irregular tiling of mixed shells. Our work expands the known assembly modes of HK97-fold proteins and lays the foundation for future functional and engineering studies on two-component encapsulins. Icosahedral symmetry ; Component (thermodynamics) ; Composition (language) ; Quasicrystal ; Shell (structure) ; Crystallography ; Variable (mathematics) ; Materials science ; Combinatorics ; Geometry ; Mathematics ; Physics ; Chemistry ; Mathematical analysis ; Composite material ; Thermodynamics ; Art Enzyme Structure and Function ; Supramolecular Self-Assembly in Materials ; Proteins in Food Systems
Authors: Vrouyr Bilemjian | Yusheng Lin | Wei Wan | Gabriella Egri | Gerwin Huls | Thomas Heinze | Edwin Bremer | Martin Gericke | Lars Dähne
Source: ChemBioChem (article, 2024-01-18)
Field: Materials Science — Biomaterials

Direct Functionalization of Polysaccharide‐Based Xylan Phenyl Carbonate Nanoparticles with Tumor Cell Specific Antibodies An efficient and easy-to-use approach is presented for obtaining biocompatible polysaccharide-based nanoparticles (NP) that can act as tumor-specific drug delivery agents. Two antibodies are directly immobilized onto reactive xylan phenyl carbonate (XPC) NP; namely Cetuximab (CTX) that binds to human epidermal growth factor receptor (EGFR) and Atezolizumab (ATZ) that binds to programmed death-ligand 1 (PD-L1). High coupling efficiency (up to 100 %) are achieved without any pre-activation and no aggregation occurs during antibody immobilization. By quartz crystal microbalance experiments with dissipation monitoring (QCM-D), flow cytometry assays, and confocal laser scanning microscopy imaging it is demonstrated that the functionalized XPC-NP specifically bind to cells carrying the corresponding antigens. Moreover, the NP retain the antibody specific bioactivities (growth inhibition for CTX and induction of T-cell cytotoxicity for ATZ). Surface modification ; Polysaccharide ; Chemistry ; Nanoparticle ; Antibody ; Xylan ; Combinatorial chemistry ; Bioconjugation ; Biochemistry ; Nanotechnology ; Materials science ; Biology ; Immunology biodegradable polymer synthesis and properties ; Nanoparticle-Based Drug Delivery ; Electrospun Nanofibers in Biomedical Applications
Authors: Yue Yang | Yumin Wang | Chunqing He | Zheng Wang | Xiangyang Peng | Pengfei Fang
Source: Materials (article, 2024-10-02)
Field: Materials Science — Materials Chemistry

Significantly Enhanced Corona Resistance of Epoxy Composite by Incorporation with Functionalized Graphene Oxide Enhancing the corona resistance of epoxy resin (EP) is crucial for ensuring the reliable operation of electrical equipment and power systems, and the incorporation of inorganic nanofillers into epoxy resin has shown significant potential in achieving this. In this study, functionalized graphene oxide (KHGO) was synthesized via a sol-gel method to enhance the corona resistance of EP with electrochemical impedance spectroscopy (EIS) used to assess the properties of KHGO/EP composites. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) verified the successful grafting of epoxy groups onto the GO surface. The thermal conductivity and stability of the KHGO/EP composite initially increased with KHGO content but declined when the content exceeded 1.2 wt.%. Positron annihilation lifetime spectroscopy (PALS) indicated that KHGO improved interfacial compatibility with EP compared to GO, with agglomeration occurring when KHGO content exceeded a threshold value (1.2 wt.%). EIS analysis revealed that the corona resistance of the KHGO/EP composite was optimal at a filler content of 0.9 wt.%. After corona treatment, the saturation water uptake of the 0.9 wt.% KHGO/EP composite decreased by 15% compared to pure EP with its porosity reduced to just 1/40th of that of pure EP. This study underscores that well-dispersed KHGO/EP composite exhibits excellent corona resistance property suggesting the potential for industrial applications in high-voltage equipment insulation. Materials science ; Epoxy ; Dielectric spectroscopy ; X-ray photoelectron spectroscopy ; Fourier transform infrared spectroscopy ; Composite material ; Graphene ; Composite number ; Oxide ; Thermal stability ; Chemical engineering ; Electrochemistry ; Chemistry ; Nanotechnology ; Electrode High voltage insulation and dielectric phenomena ; Dielectric materials and actuators ; Advanced Sensor and Energy Harvesting Materials
Authors: Yuqing Tan | Yumei Cao | Sam K. C. Chang
Source: Journal of Food Science (article, 2024-06-21)
Field: Materials Science — Biomaterials

Characteristics of soy films as affected by transglutaminase cross‐linking and inclusions of pectin and protein enhancers Previously, we showed that water extract (soymilk, except pH was increased to 8 from 6.5) of whole soybean could be used directly as a raw material for producing edible soy films by deposition of the film-forming solution (soy extract with enhancers). However, the strength of such soy films needed improvement because they were weak. The purpose of this study was to investigate how transglutaminase (TG) cross-linking reactions and film enhancers, including pectin (low- and high-methoxyl pectin), whey protein isolate (WPI), and soy protein isolate (SPI), improve the physical properties of soy films. Soy films prepared with TG had tensile strength (TS) of 3.01 MPa and puncture strength (PS) of 0.78 MPa, which were higher by as much as 51% and 30% than that of soy films without TG treatment, respectively. Pectin showed significant effects on the mechanical properties of TG-added soy films in terms of TS, PS, and % elongation. On the other hand, only TS and PS were increased by the addition of WPI or SPI. Heat curing had a significant effect on soy film's physical properties. TG treatment significantly reduced film solubility when soaked in water and various levels of acid (vinegar) and base (baking soda) solutions. Under the experimental conditions of 35 unit TG and 28 min of reaction, the degrees of cross-linking were evidenced by the disappearance of individual protein subunits, except the basic subunit of glycinin, and the reduction of 21% of lysine residues of the proteins. HIGHLIGHTS: Edible soy films were made with transglutaminase and about 21% lysine cross-linked. The mechanical strength of soy films was increased by incorporating film enhancers. Transglutaminase enhanced the mechanical properties of soy films. Soy protein ; Pectin ; Chemistry ; Tissue transglutaminase ; Food science ; Ultimate tensile strength ; Solubility ; Soy flour ; Elongation ; Materials science ; Biochemistry ; Enzyme ; Organic chemistry ; Composite material Nanocomposite Films for Food Packaging ; Material Properties and Processing ; Postharvest Quality and Shelf Life Management
Authors: Nishal M. Egodawaththa | Olivia Rajhel | Jingxuan Ma | Charitha Guruge | Alec B. Pabarue | E. J. Harris | Roberto Peverati | Nasri Nesnas
Source: ChemRxiv (preprint, 2024-03-07)
Field: Materials Science — Materials Chemistry

Highly Efficient Visible Light-Induced Ca2+ Chelation Calcium ion (Ca2+) control is an essential tool in neuronal research. Herein, we report three thiocoumarin-based, visi-ble light-activated Ca2+ chelators with high quantum yields of 0.39, 0.52, and 0.83. The chelators demonstrated an over 10^5-fold increase in Ca2+ binding affinity upon irradiation. These chelators are efficiently triggered by biologically safer wavelengths, rendering them excellent candidates for use in neuroscientific research and medicine. Chelation ; Chemistry ; Computer science ; Inorganic chemistry Luminescence and Fluorescent Materials ; Photochromic and Fluorescence Chemistry ; Nanocluster Synthesis and Applications
Authors: Natsuki Mitsuishi | K. Ishizaka
Source: Journal of the Physical Society of Japan (article, 2024-09-27)
Field: Materials Science — Materials Chemistry

Electronic Landscape of Group-5 Transition Metal Ditellurides <i>M</i>Te<sub>2</sub> (<i>M</i> = V, Nb, Ta): Multiple Crystal Phases with Local Bonds and Flat Bands Group-5 transition metal ditellurides $M$Te$_2$ ($M$ = V, Nb, Ta) are unique CdI$_2$-type layered materials that exhibit peculiar quasi-one-dimensional intralayer superstructures, known as ribbon-chains and butterfly-like clusters of $M$ atoms. In this review article, we attempt to systematically understand their electronic band structures based on our recent angle-resolved photoemission spectroscopy (ARPES) studies and first-principles calculations. We underscore the role of the localized molecular-like orbital bonds that form the anomalous flat bands in the momentum space, and demonstrate how they influence the Fermi surface anisotropy, phase stabilities of crystal structures, and nontrivial topological properties in some cases. We also elaborate the future prospects for novel quantum phenomena that can be realized in these materials. Transition metal ; Group (periodic table) ; Crystal (programming language) ; Materials science ; Electronic structure ; Crystallography ; Crystal structure ; Condensed matter physics ; Physics ; Atomic physics ; Chemistry ; Computer science ; Quantum mechanics 2D Materials and Applications ; Perovskite Materials and Applications ; Inorganic Chemistry and Materials
Authors: Sanskruti Swain | Ting‐Yi Lin | I-Hsuan Chou | Shu‐Chen Liu | Bikash Chandra Mallick | Hsing-Ying Lin | Chen-Han Huang
Source: Journal of Nanobiotechnology (article, 2024-09-28)
Field: Materials Science — Materials Chemistry

Photoactive nanocatalysts as DTT-assisted BSA-AuNCs with enhanced oxidase-mimicking ability for sensitive fluorometric detection of antioxidants Redox imbalance and oxidative stress are increasingly recognized as significant factors in health disorders such as neurodegenerative disorders, premature aging and cancer. However, detecting antioxidant levels that is crucial for managing oxidative stress, can be challenging due to existing assays' limitations, such as insensitivity to thiol-containing antioxidants. This study presents a simple fluorescence-based assay for antioxidant detection employing the enhanced photocatalytic oxidase-like activity of dithiothreitol (DTT)-assisted bovine serum albumin (BSA)-stabilized gold nanoclusters (DTT@BSA-AuNCs). The reported nanozyme exhibits remarkable stability, versatility, and catalytic activity. Under LED irradiation, DTT@BSA-AuNCs generate singlet oxygen, which converts non-fluorescent thiamine to fluorescent thiochrome, utilizing dissolved oxygen for catalysis. Antioxidants inhibit thiochrome formation, leading to fluorescence quenching. This method enables sensitive detection of antioxidants such as ascorbic acid and glutathione with limits of detection of 0.08 µM and 0.32 µM, respectively, under neutral pH, outperforming previous studies. The assay successfully detects antioxidants in human saliva and cancer cell models. The DTT@BSA-AuNCs-based assay offers a cost-effective, sensitive, and straightforward approach for detecting antioxidants in biological samples, facilitating improved monitoring of oxidative stress in various diseases. Chemistry ; Fluorescence ; Nanomaterial-based catalyst ; Biophysics ; Nanotechnology ; Photochemistry ; Biochemistry ; Materials science ; Biology Advanced Nanomaterials in Catalysis ; Electrochemical sensors and biosensors ; Nanocluster Synthesis and Applications
Authors: Luis Angel Alvarado-Leal | J. I. Páez-Ornelas | M. A. Ruiz-Robles | J. Guerrero-Sánchez | J. M. Romo-Herrera | H. N. Fernández-Escamilla | Noboru Takeuchi | E. Peréz‐Tijerina
Source: Nanoscale (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Exploring nitrogen-mediated effects on Fe and Cu cluster development in graphene: a DFT study The controlled growth and stability of transition metal clusters on N-doped materials have become the subject of intense investigation for unveiling comprehension on the cluster growth evolution. In this study, we investigated the growth mechanisms of non-magnetic (copper) and magnetic (iron) clusters on graphene with two atomic vacancies, with and without pyridinic nitrogen (N). Our results determine the role of pyridinic N in the growth and physicochemical properties of the mentioned metal clusters. In an N environment, Cu grows perpendicularly, whereas under N-deficient conditions, the clusters agglomerate. Fe cumulate-type clusters are formed regardless of the presence of N. However, N causes the Fe clusters to rise over one side of the surface without deforming the monolayer; meanwhile, in the absence of N, the Fe clusters protrude from both sides of the monolayer. Remarkably, the presence of N makes it feasible to induce magnetization in the Cu<sub><i>n</i></sub>-N<sub>4</sub>V<sub>2</sub> systems and aid in focalizing the magnetic properties on the Fe clusters for the Fe<sub><i>n</i></sub>-N<sub>4</sub>V<sub>2</sub> case. These findings offer insights into the role of N in cluster growth, with potential implications for diverse applications, including magnetic and electrocatalytic materials. Graphene ; Cluster (spacecraft) ; Materials science ; Nitrogen ; Nanotechnology ; Chemical physics ; Chemistry ; Computer science ; Organic chemistry Graphene research and applications ; Advancements in Battery Materials ; Catalytic Processes in Materials Science
Authors: Ryo Fukumoto | Eri Sakuda | Kenichiro Omoto | Shinnosuke Horiuchi | Yasuhiro Arikawa | Keisuke Umakoshi
Source: Chemistry Letters (article, 2024-11-29)
Field: Materials Science — Materials Chemistry

Increased phosphorescence of cyclometalated Ir(III) complex with a planar triarylborane moiety upon fluoride anion binding Abstract A luminescent Ir(III) complex functionalized with a planar triarylborane moiety was prepared. This complex exhibits unique photophysical properties derived from the electron-withdrawing effect of the triarylborane moiety. A significant change in electron density occurs upon binding of F– to the electron-deficient boron center, resulting in decreased absorption and enhanced emission. Chemistry ; Moiety ; Phosphorescence ; Fluoride ; Ion ; Photochemistry ; Polymer chemistry ; Medicinal chemistry ; Stereochemistry ; Inorganic chemistry ; Organic chemistry ; Fluorescence Luminescence and Fluorescent Materials ; Organoboron and organosilicon chemistry ; Catalytic Cross-Coupling Reactions
Authors: Tadashi Mori
Source: Angewandte Chemie (article, 2024-02-07)
Field: Chemistry — Organic Chemistry

Significance of Vibronic Coupling that Shapes Circularly Polarized Luminescence of Double Helicenes Abstract The circularly polarized luminescence (CPL) spectra of S ‐ and X ‐shaped double helicenes exhibit distinct vibrational structures and overall shape variations. In this study, we conducted an in‐depth investigation into the vibronic effects influencing the CPL spectra of two double helicenes, namely DPC and DNH . Employing state‐of‐the‐art computations utilizing the FC‐HT 1 |VH model at the CAM−B3LYP/def2‐TZVP level, we unveiled the paramount impact of Franck–Condon (FC), Herzberg‐Teller (HT), and Duschinsky effects on their chiroptical responses. Our research underscores the pivotal role of structural deformations associated with the S 1 ‐to‐S 0 electronic transition in molding CPL spectra and wavelength‐dependent dissymmetry ( g ) factor values, as well as the significance of HT effects in shaping and enhancing CPL responses. This extensive investigation not only advances our comprehension of the vibronic characteristics in configurationally distinct double helicenes but also offers valuable insights for the design of chiral molecules featuring controllable or finely‐tunable CPL responses. Luminescence ; Vibronic coupling ; Coupling (piping) ; Vibronic spectroscopy ; Molecular physics ; Circular polarization ; Physics ; Chemistry ; Materials science ; Photochemistry ; Atomic physics ; Optics ; Excited state Synthesis and Properties of Aromatic Compounds ; Luminescence and Fluorescent Materials ; Fullerene Chemistry and Applications
Authors: Kyunghyun Eun | Sang-Min Yoon | Changjae Lee | Gayoung Kim | Jaesung Yang | Byung Jun Jung | Jin‐Kyun Lee | Myungwoong Kim
Source: Advanced Functional Materials (article, 2024-12-08)
Field: Materials Science — Polymers and Plastics

Embodiment of Light‐Mediated Main‐Chain Scissionable Functionality While Preserving the Structure of Conventional Photoimaging Copolymer Abstract The rational design and development of a main‐chain scissionable functional copolymer platform is reported by incorporating a photocleavable nitrobenzyl ester group into the middle of the copolymer backbone while fully preserving its overall structure and function for photopatterning applications on delicate organic semiconductor films. As a model system, a positive‐tone photoimaging fluoroalkyl copolymer is used containing a photoisomerizable spiropyranyl unit. The nitrobenzyl ester functionality degrades under UV light and enhances solubility modulation and photopatternability by reducing chain length. This behavior is systematically studied across copolymers with varying, yet narrowly distributed, molecular weights. To further improve the sensitivity of the photoimaging copolymer, it is demonstrated that minimal structural modification of the cleavable group, specifically altering the positions of the methoxy and nitro groups, are highly effective. Finally, a square array of a chemically susceptible organic electron transport material, suitable for organic light‐emitting diodes (OLEDs), is fabricated using the copolymer through conventional lithography and pattern transfer processes. This work highlights the importance of rationally designing main‐chain scission‐type light‐sensitive materials that maintain the core structure of conventional materials, making them highly compatible and desirable for standard organic electronic device fabrication processes. Copolymer ; Materials science ; OLED ; Fabrication ; Side chain ; Lithography ; Nanotechnology ; Chemical engineering ; Polymer ; Optoelectronics ; Composite material ; Layer (electronics) Synthesis and properties of polymers ; Advanced Polymer Synthesis and Characterization ; Organic Electronics and Photovoltaics
Authors: Tomohito Shinozuka | Daiki Shimizu | Kenji Matsuda
Source: New Journal of Chemistry (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

Theoretical investigation of the effect of radical substituents on the open-shell character of polycyclic aromatic hydrocarbons Radical substituents was found to significantly alter the open-shell character y of PAHs compared to non-radical substituents. Chemistry ; Character (mathematics) ; Polycyclic aromatic hydrocarbon ; Hydrocarbon ; Open shell ; Shell (structure) ; Computational chemistry ; Photochemistry ; Organic chemistry Free Radicals and Antioxidants ; Synthesis and Properties of Aromatic Compounds ; Advanced Chemical Physics Studies
Authors: Lingyu Liu | Linyan Wang | Pan Ying | Meng Hu | Yueqing Li | Fanggong Cai | Qinyong Zhang
Source: iScience (article, 2024-08-30)
Field: Materials Science — Materials Chemistry

A superhard incompressible carbon allotrope with deformation-induced transformation to diamond Recognizing the indispensability of hard materials in industrial applications, the persistent pursuit of ultra-strong and superhard materials has been a subject of extensive research. Carbon, with its versatile hybridization possibilities, emerges as a promising avenue for the creation of such materials. Herein, based on first-principles calculations, we predict an all-<i>sp</i> <sup>3</sup> hybrid orthorhombic carbon allotrope named C<sub>10</sub>. It exhibits greater incompressibility along the [010] direction than diamond, demonstrating an extreme hardness with Vickers hardness of up to 72.8 GPa. The Young's modulus of C<sub>10</sub> displays anisotropy, closely comparable to diamond along the x axis direction, while maintaining excellent mechanical stability within the range of 100 GPa. Notably, under the influence of shear force, it undergoes transformation into diamond. Functioning as a transparent semiconductor with a wide indirect band gap of 4.55 eV, C<sub>10</sub> holds promise as a potential superhard material in the semiconductor industry, especially under extreme conditions. Diamond ; Carbon fibers ; Compressibility ; Transformation (genetics) ; Materials science ; Deformation (meteorology) ; Nanotechnology ; Engineering physics ; Chemistry ; Physics ; Thermodynamics ; Composite material Boron and Carbon Nanomaterials Research ; Diamond and Carbon-based Materials Research ; Fullerene Chemistry and Applications
Authors: María Belén Rivas Aiello | Thomas M. Kirse | Gabriel C. Lavorato | Bastian Maus | Iván Maisuls | Shivadharshini Kuberasivakumaran | Stefan Ostendorp | Alexander Hepp | Michael Holtkamp | E. Winkler | Uwe Kärst | Gerhard Wilde | Cornelius Faber | Carolina Vericat | Cristian A. Strassert
Source: Small Science (article, 2024-01-12)
Field: Materials Science — Materials Chemistry

Superparamagnetic Nanoparticles with Phosphorescent Complexes as Hybrid Contrast Agents: Integration of MRI and PLIM Two different hybrid nanosystems are prepared by loading highly crystalline, monodisperse magnetite nanocubes (MNCs) with phosphorescent Pt(II) complexes (PtCxs). One involves the encapsulation of the hydrophobic PtCx1 within an amphiphilic comb polymer (MNC@poly(maleic anhydride-<i>alt</i>-1-octadecene) [PMAO]-PtCx1), whereas the other involves the direct binding of the hydrophilic PtCx2 to the surface of the MNC mediated by a ligand-exchange procedure (MNC@OH-PtCx2). Both systems are evaluated as potential candidates for multimodal imaging in magnetic resonance imaging (MRI) and photoluminescence lifetime imaging micro(spectro)scopy (PLIM). PLIM measurements on agarose phantoms demonstrate significantly longer excited-state lifetimes compared to the short-lived autofluorescence of biological background. Additionally, both nanosystems perform as effective MRI contrast agents (CAs): the <i>r</i> <sub>2</sub>* values are 3-4 times higher than for the commercial CA ferucarbotran. MNC@PMAO-PtCx1 particles also cause significant increases in <i>r</i> <sub>2</sub>. While the ligand exchange procedure efficiently anchors PtCxs to the MNC surface, the polymeric encapsulation ensures higher colloidal stability, contributing to differences in PLIM and MRI outcomes. In these results, the successful integration of two complementary noninvasive imaging modalities within a single nanosystem is confirmed, serving as the impetus for further investigation of such systems as advanced multimodal-multiscale imaging agents with dual orthogonal readouts. Nanoparticle ; Materials science ; Autofluorescence ; Magnetic resonance imaging ; Magnetite Nanoparticles ; Nuclear magnetic resonance ; Nanotechnology ; Chemistry ; Biomedical engineering ; Magnetic nanoparticles ; Fluorescence ; Optics ; Medicine Lanthanide and Transition Metal Complexes ; Advanced MRI Techniques and Applications ; Nanoplatforms for cancer theranostics