jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Marino F. A. Santos | João Costa Pessoa
Source: Molecules (review, 2023-09-09)
Field: Chemistry — Inorganic Chemistry

Interaction of Vanadium Complexes with Proteins: Revisiting the Reported Structures in the Protein Data Bank (PDB) since 2015 The structural determination and characterization of molecules, namely proteins and enzymes, is crucial to gaining a better understanding of their role in different chemical and biological processes. The continuous technical developments in the experimental and computational resources of X-ray diffraction (XRD) and, more recently, cryogenic Electron Microscopy (cryo-EM) led to an enormous growth in the number of structures deposited in the Protein Data Bank (PDB). Bioinorganic chemistry arose as a relevant discipline in biology and therapeutics, with a massive number of studies reporting the effects of metal complexes on biological systems, with vanadium complexes being one of the relevant systems addressed. In this review, we focus on the interactions of vanadium compounds (VCs) with proteins. Several types of binding are established between VCs and proteins/enzymes. Considering that the V-species that bind may differ from those initially added, the mentioned structural techniques are pivotal to clarifying the nature and variety of interactions of VCs with proteins and to proposing the mechanisms involved either in enzymatic inhibition or catalysis. As such, we provide an account of the available structural information of VCs bound to proteins obtained by both XRD and/or cryo-EM, mainly exploring the more recent structures, particularly those containing organic-based vanadium complexes. Protein Data Bank ; Protein Data Bank (RCSB PDB) ; Vanadium ; Bioinorganic chemistry ; Structural biology ; Chemistry ; Protein–protein interaction ; Protein structure ; Enzyme ; Structural bioinformatics ; Computational biology ; Characterization (materials science) ; Biochemistry ; Nanotechnology ; Crystallography ; Biology ; Materials science ; Organic chemistry Vanadium and Halogenation Chemistry ; Metal-Catalyzed Oxygenation Mechanisms ; Trace Elements in Health
Authors: Daniel W. Armstrong | Alain Berthod
Source: Natural Products and Bioprospecting (review, 2023-11-07)
Field: Chemistry — Organic Chemistry

Occurrence of D-amino acids in natural products Since the identified standard genetic code contains 61 triplet codons of three bases for the 20 L-proteinogenic amino acids (AAs), no D-AA should be found in natural products. This is not what is observed in the living world. D-AAs are found in numerous natural compounds produced by bacteria, algae, fungi, or marine animals, and even vertebrates. A review of the literature indicated the existence of at least 132 peptide natural compounds in which D-AAs are an essential part of their structure. All compounds are listed, numbered and described herein. The two biosynthetic routes leading to the presence of D-AA in natural products are: non-ribosomal peptide synthesis (NRPS), and ribosomally synthesized and post-translationally modified peptide (RiPP) synthesis which are described. The methods used to identify the AA chirality within naturally occurring peptides are briefly discussed. The biological activity of an all-L synthetic peptide is most often completely different from that of the D-containing natural compounds. Analyzing the selected natural compounds showed that D-Ala, D-Val, D-Leu and D-Ser are the most commonly encountered D-AAs closely followed by the non-proteinogenic D-allo-Thr. D-Lys and D-Met were the least prevalent D-AAs in naturally occurring compounds. Plant biochemistry ; Bioorganic chemistry ; Amino acid ; Natural (archaeology) ; Chemistry ; Natural Product Research ; Biochemical engineering ; Biochemistry ; Biology ; Engineering ; Enzyme ; Pharmacognosy Carbohydrate Chemistry and Synthesis ; Microbial Natural Products and Biosynthesis ; Chemical Synthesis and Analysis
Authors: Anna Vaisman | Yuval Vidavsky | Mark Baranov | Avi Lehrer | Joshua H. Baraban | N. Gabriel Lemcoff
Source: Journal of the American Chemical Society (article, 2023-12-21)
Field: Chemistry — Organic Chemistry

Latency for All: Enabling Latency of Hoveyda–Grubbs Second-Generation Catalysts by Adding Phosphite Ligands The Hoveyda-Grubbs catalyst (<b>HG2</b>, M720 Umicore) is among the most widely used catalysts in olefin metathesis reactions. Given the usefulness of <b>HG2</b> and the great interest in developing latent olefin metathesis catalysts for numerous applications, we developed a method to introduce phosphite molecules as ancillary ligands into the precatalyst framework. This modification alters the geometry of the complex from an active <i>trans</i>-dichloro form to a latent <i>cis</i>-dichloro species. Most unusually, the ligands coordinate to <b>HG2</b> only in solidified solutions (most likely due to entropic factors), providing latent catalysts that can be activated on demand by heat or light by regenerating the original <b>HG2</b> catalyst. Of particular interest is the use of these latent catalysts in ring-opening metathesis polymerization (ROMP) reactions and 3D printing methods. Indeed, the novel complexes displayed the required latency toward ROMP monomers, even the most reactive dicyclopentadiene. Irradiation with 405 nm light readily results in the expedited formation of the desired polymers. This novel approach provides a general and straightforward way to access efficient and well-defined latent olefin metathesis catalysts. ROMP ; Chemistry ; Catalysis ; Dicyclopentadiene ; Metathesis ; Polymerization ; Salt metathesis reaction ; Ring-opening metathesis polymerisation ; Combinatorial chemistry ; Ruthenium ; Olefin metathesis ; Monomer ; Polymer chemistry ; Polymer ; Organic chemistry Synthetic Organic Chemistry Methods ; Chemical Synthesis and Analysis ; Organometallic Complex Synthesis and Catalysis
Authors: Yazhen Xue | Mengxue Cao | Charles Chen | Mingjiang Zhong
Source: JACS Au (review, 2023-04-27)
Field: Chemistry — Organic Chemistry

Design of Microstructure-Engineered Polymers for Energy and Environmental Conservation With the ever-growing demand for sustainability, designing polymeric materials using readily accessible feedstocks provides potential solutions to address the challenges in energy and environmental conservation. Complementing the prevailing strategy of varying chemical composition, engineering microstructures of polymer chains by precisely controlling their chain length distribution, main chain regio-/stereoregularity, monomer or segment sequence, and architecture creates a powerful toolbox to rapidly access diversified material properties. In this Perspective, we lay out recent advances in utilizing appropriately designed polymers in a wide range of applications such as plastic recycling, water purification, and solar energy storage and conversion. With decoupled structural parameters, these studies have established various microstructure-function relationships. Given the progress outlined here, we envision that the microstructure-engineering strategy will accelerate the design and optimization of polymeric materials to meet sustainability criteria. Energy conservation ; Microstructure ; Materials science ; Biochemical engineering ; Engineering ; Ecology ; Composite material ; Biology Advanced Polymer Synthesis and Characterization ; biodegradable polymer synthesis and properties ; Polymer composites and self-healing
Authors: Farkhondeh Mohammad Aminzadeh | Behzad Zeynizadeh
Source: Nanoscale Advances (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

Immobilized nickel boride nanoparticles on magnetic functionalized multi-walled carbon nanotubes: a new nanocomposite for the efficient one-pot synthesis of 1,4-benzodiazepines In this study, a new magnetic nanocomposite consisting of Ni<sub>2</sub>B nanoparticles anchored on magnetic functionalized multi-walled carbon nanotubes (Fe<sub>3</sub>O<sub>4</sub>/f-MWCNT/Ni<sub>2</sub>B) was synthesized and characterized using various techniques such as FT-IR, XRD, FESEM, SEM-based EDX, SEM-based elemental mapping, HRTEM, DLS, SAED, XPS, BET, TGA, and VSM. The as-prepared magnetic nanocomposite was successfully employed for the preparation of bioactive 1,4-benzodiazepines from the three-component reaction of <i>o</i>-phenylenediamine (1), dimedone (2), and different aldehydes (3), in polyethylene glycol 400 (PEG-400) as a solvent at 60 °C. The obtained results demonstrated that the current one-pot three-component protocol offers many advantages, such as good-to-excellent yields within acceptable reaction times, favorable TONs and TOFs, eco-friendliness of the procedure, easy preparation of the nanocomposite, mild reaction conditions, a broad range of products, excellent catalytic activity, green solvent, and reusability of the nanocomposite. Nanocomposite ; Materials science ; Carbon nanotube ; High-resolution transmission electron microscopy ; Chemical engineering ; Polyethylene glycol ; Catalysis ; Nanoparticle ; Nuclear chemistry ; Magnetic nanoparticles ; Solvent ; Nanotechnology ; Organic chemistry ; Chemistry ; Transmission electron microscopy Multicomponent Synthesis of Heterocycles ; Synthesis of Tetrazole Derivatives ; Synthesis and Biological Evaluation
Authors: Xiaofang Zhang | Fangling Li | Shuangqiao Yang | Baiqi Song | Richu Luo | Rui Xiong | Weilin Xu
Source: SusMat (article, 2023-12-28)
Field: Materials Science — Materials Chemistry

Multi‐scale structure engineering of covalent organic framework for electrochemical charge storage Abstract Covalent organic frameworks (COFs), which are constructed by linking organic building blocks via dynamic covalent bonds, are newly emerged and burgeoning crystalline porous copolymers with features including programmable topological architecture, pre‐designable periodic skeleton, well‐defined micro‐/meso‐pore, large specific surface area, and customizable electroactive functionality. Those benefits make COFs as promising candidates for advanced electrochemical energy storage. Especially, for now, structure engineering of COFs from multi‐scale aspects has been conducted to enable optimal overall electrochemical performance in terms of structure durability, electrical conductivity, redox activity, and charge storage. In this review, we give a fundamental and insightful study on the correlations between multi‐scale structure engineering and eventual electrochemical properties of COFs, started with introducing their basic chemistries and charge storage principles. The careful discussion on the significant achievements in structure engineering of COFs from linkages, redox sites, polygon skeleton, crystal nanostructures, and composite microstructures, and further their effects on the electrochemical behavior of COFs are presented. Finally, the timely cutting‐edge perspectives and in‐depth insights into COF‐based electrode materials to rationally screen their electrochemical behaviors for addressing future challenges and implementing electrochemical energy storage applications are proposed. Electrochemical energy storage ; Electrochemistry ; Materials science ; Energy storage ; Covalent bond ; Nanotechnology ; Electrode ; Supercapacitor ; Chemistry ; Organic chemistry ; Physics Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Conducting polymers and applications
Authors: Natalia Łopuszyńska | Władysław P. Węglarz
Source: Nanomaterials (review, 2023-07-25)
Field: Materials Science — Materials Chemistry

Contrasting Properties of Polymeric Nanocarriers for MRI-Guided Drug Delivery Poor pharmacokinetics and low aqueous solubility combined with rapid clearance from the circulation of drugs result in their limited effectiveness and generally high therapeutic doses. The use of nanocarriers for drug delivery can prevent the rapid degradation of the drug, leading to its increased half-life. It can also improve the solubility and stability of drugs, advance their distribution and targeting, ensure a sustained release, and reduce drug resistance by delivering multiple therapeutic agents simultaneously. Furthermore, nanotechnology enables the combination of therapeutics with biomedical imaging agents and other treatment modalities to overcome the challenges of disease diagnosis and therapy. Such an approach is referred to as "theranostics" and aims to offer a more patient-specific approach through the observation of the distribution of contrast agents that are linked to therapeutics. The purpose of this paper is to present the recent scientific reports on polymeric nanocarriers for MRI-guided drug delivery. Polymeric nanocarriers are a very broad and versatile group of materials for drug delivery, providing high loading capacities, improved pharmacokinetics, and biocompatibility. The main focus was on the contrasting properties of proposed polymeric nanocarriers, which can be categorized into three main groups: polymeric nanocarriers (1) with relaxation-type contrast agents, (2) with chemical exchange saturation transfer (CEST) properties, and (3) with direct detection contrast agents based on fluorinated compounds. The importance of this aspect tends to be downplayed, despite its being essential for the successful design of applicable theranostic nanocarriers for image-guided drug delivery. If available, cytotoxicity and therapeutic effects were also summarized. Nanocarriers ; Drug delivery ; Drug ; Nanomedicine ; Nanotechnology ; Biocompatibility ; Targeted drug delivery ; Pharmacokinetics ; Pharmacology ; Materials science ; Biomedical engineering ; Medicine ; Nanoparticle Lanthanide and Transition Metal Complexes ; Nanoparticle-Based Drug Delivery ; MRI in cancer diagnosis
Authors: Hélène Pellissier
Source: Coordination Chemistry Reviews (article, 2023-02-21)
Field: Chemistry — Inorganic Chemistry

TADDOL-derived phosphorus ligands in asymmetric catalysis Chemistry ; Enantioselective synthesis ; Phosphorus ; Catalysis ; Combinatorial chemistry ; Metal ; Organic chemistry Asymmetric Hydrogenation and Catalysis ; Asymmetric Synthesis and Catalysis ; Synthetic Organic Chemistry Methods
Authors: Parth Mehta | Pravin Shende
Source: Cell Biochemistry and Function (review, 2023-11-06)
Field: Materials Science — Biomaterials

Evasion of opsonization of macromolecules using novel surface‐modification and biological‐camouflage‐mediated techniques for next‐generation drug delivery Opsonization plays a pivotal role in hindering controlled drug release from nanoformulations due to macrophage-mediated nanoparticle destruction. While first and second-generation delivery systems, such as lipoplexes (50-150 nm) and quantum dots, hold immense potential in revolutionizing disease treatment through spatiotemporal controlled drug delivery, their therapeutic efficacy is restricted by the selective labeling of nanoparticles for uptake by reticuloendothelial system and mononuclear phagocyte system via various molecular forces, such as electrostatic, hydrophobic, and van der Waals bonds. This review article presents novel insights into surface-modification techniques utilizing macromolecule-mediated approaches, including PEGylation, di-block copolymerization, and multi-block polymerization. These techniques induce stealth properties by generating steric forces to repel micromolecular-opsonins, such as fibrinogen, thereby mitigating opsonization effects. Moreover, advanced biological methods, like cellular hitchhiking and dysopsonic protein adsorption, are highlighted for their potential to induce biological camouflage by adsorbing onto the nanoparticulate surface, leading to immune escape. These significant findings pave the way for the development of long-circulating next-generation nanoplatforms capable of delivering superior therapy to patients. Future integration of artificial intelligence-based algorithms, integrated with nanoparticle properties such as shape, size, and surface chemistry, can aid in elucidating nanoparticulate-surface morphology and predicting interactions with the immune system, providing valuable insights into the probable path of opsonization. Antibody opsonization ; Nanotechnology ; Drug delivery ; Mononuclear phagocyte system ; PEGylation ; Chemistry ; Nanoparticle ; Internalization ; Macromolecule ; Biophysics ; Materials science ; Opsonin ; Polyethylene glycol ; Biology ; Biochemistry ; Cell ; Immunology Nanoparticle-Based Drug Delivery ; Advancements in Transdermal Drug Delivery ; Advanced Drug Delivery Systems
Authors: Christian Tantardini | Alexander G. Kvashnin | Maryam Azizi | Xavier Gonze | Carlo Gatti | Tariq Altalhi | Boris I. Yakobson
Source: ACS Applied Materials & Interfaces (article, 2023-03-16)
Field: Materials Science — Materials Chemistry

Electronic Properties of Functionalized Diamanes for Field-Emission Displays Ultrathin diamond films, or diamanes, are promising quasi-2D materials that are characterized by high stiffness, extreme wear resistance, high thermal conductivity, and chemical stability. Surface functionalization of multilayer graphene with different stackings of layers could be an interesting opportunity to induce proper electronic properties into diamanes. Combination of these electronic properties together with extraordinary mechanical ones will lead to their applications as field-emission displays substituting original devices with light-emitting diodes or organic light-emitting diodes. In the present study, we focus on the electronic properties of fluorinated and hydrogenated diamanes with (111), (110), (0001), (101̅0), and (2̅110) crystallographic orientations of surfaces of various thicknesses by using first-principles calculations and Bader analysis of electron density. We see that fluorine induces an occupied surface electronic state, while hydrogen modifies the occupied bulk state and also induces unoccupied surface states. Furthermore, a lower number of layers is necessary for hydrogenated diamanes to achieve the convergence of the work function in comparison with fluorinated diamanes, with the exception of fluorinated (110) and (2̅110) films that achieve rapid convergence and have the same behavior as other hydrogenated surfaces. This induces a modification of the work function with an increase of the number of layers that makes hydrogenated (2̅110) diamanes the most suitable surface for field-emission displays, better than the fluorinated counterparts. In addition, a quasi-quantitative descriptor of surface dipole moment based on the Tantardini-Oganov electronegativity scale is introduced as the average of bond dipole moments between the surface atoms. This new fundamental descriptor is capable of predicting a priori the bond dipole moment and may be considered as a new useful feature for crystal structure prediction based on artificial intelligence. Materials science ; Work function ; Electronegativity ; Dipole ; Surface modification ; Field electron emission ; Chemical physics ; Electronic structure ; Nanotechnology ; Optoelectronics ; Electron ; Computational chemistry ; Chemical engineering Diamond and Carbon-based Materials Research ; Graphene research and applications ; Boron and Carbon Nanomaterials Research
Authors: Amir Alipasandi | Asghar Mahmoudi | Barbara Sturm | Hossein Behfar | Saman Zohrabi
Source: Computers and Electronics in Agriculture (article, 2023-01-06)
Field: Chemistry — Analytical Chemistry

Application of meta-heuristic feature selection method in low-cost portable device for watermelon classification using signal processing techniques Support vector machine ; Computer science ; Feature selection ; Artificial intelligence ; Pattern recognition (psychology) ; Signal processing ; k-nearest neighbors algorithm ; Wavelet ; Mahalanobis distance ; Naive Bayes classifier ; Data mining ; Mathematics ; Digital signal processing Spectroscopy and Chemometric Analyses ; Smart Agriculture and AI ; Advanced Chemical Sensor Technologies
Authors: Xudong Fang | Hao Sun | Chen Wu | Ziyan Fang | Min Li | Libo Zhao | Bian Tian | Prateek Verma | Jiuhong Wang | Ryutaro Maeda | Zhuangde Jiang
Source: ACS Applied Materials & Interfaces (article, 2023-05-31)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Ag Nanoparticle-Thiolated Chitosan Composite Coating Reinforced by Ag–S Covalent Bonds with Excellent Electromagnetic Interference Shielding and Joule Heating Performances Conductive composite coatings are an important element in flexible electronics research and are widely used in energy transformation, artificial intelligence, and electronic skins. However, the comparatively low electrical conductivity limits their performance in many specific applications, such as electromagnetic interference (EMI) shielding and Joule heating devices. Therefore, the preparation of ultrahigh-electrical conductivity composite coatings with good flexibility and durability remains a great challenge. Herein, we fabricated multifunctional conductive composite coatings based on thiolated chitosan (TCS) and Ag nanoparticles (AgNPs) by an eco-friendly drop-coating method. The three-dimensional conductive network constructed by thermal sintering imparted the coating with an ultrahigh electrical conductivity of up to 67079.4 S/m. Moreover, the coating reinforced by Ag-S covalent bonding exhibits good stability, including heat resistance, chemical resistance, and mechanical stability. In addition, based on the ultrahigh electrical conductivity, the coating exhibits superior EMI shielding effectiveness and Joule heating capability. With 30 wt % of AgNPs in the coating, the EMI shielding effectiveness of the coating reaches 70.2 dB, far exceeding commercial standards. Additionally, the coating can quickly reach a saturation temperature (<i>T</i><sub>s</sub>) of 195.9 °C at a safe drive voltage of 3 V. These excellent performances demonstrate that the robust and flexible highly conductive composite coatings prepared by this method have attractive potential for EMI shielding and thermal management applications as well as in wearable electronics. Materials science ; Coating ; Composite material ; Electromagnetic shielding ; Composite number ; Joule heating ; Electrical conductor Electromagnetic wave absorption materials ; Advanced Sensor and Energy Harvesting Materials ; Dielectric materials and actuators
Authors: Munazza Ramzan | Malika Rani | Rabia Siddiqui | Aqeel Ahmed Shah | Maryam Arshad | M. Ghauri | Ghazanfar Abbas | Kareem Yusuf | Mika Sillanpää
Source: Heliyon (article, 2023-10-20)
Field: Chemistry — Inorganic Chemistry

Synthesis and analytical characterization of Ca-BTC metal organic framework Metal Organic framework (MOF) has been a class of great interest during the past few years owing to its decidedly applicative, easily synthesized and improved characteristics. Ca-BTC MOF is synthesized by Hydrothermal technique and reported for the first time. Its structural morphology was analyzed using XRD, SEM, and EDS, showing the tetragonal crystal structure having grain size of 24.92 nm and purity of sample respectively. FTIR, Raman Spectroscopy ensures the metal organic framework between Calcium and the tri-carboxylic group. Photoluminescence measures the energy gap of 3.792 eV, showing approximately the semiconducting behavior of synthesized material. Zeta potential having value of -13.5 mV confirms the instability having good microbial activity and conductivity i.e 0.290 mS/cm which reveals important insights into its electrical properties. Characterization (materials science) ; Metal-organic framework ; Environmental chemistry ; Chemistry ; Mineralogy ; Environmental science ; Chemical engineering ; Analytical Chemistry (journal) ; Materials science ; Engineering ; Nanotechnology ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Zeolite Catalysis and Synthesis