jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Nathália Telles Paschoal Santos | Luana S. Gomes | Ruan C. B. Ribeiro | Alcione Silva de Carvalho | Maria Cristina S. Lourenço | Laís M Marins | Sandy Polycarpo Valle | Thiago Henrique Doring | Adriano D. Andricopulo | Aldo Sena de Oliveira | Vı́tor F. Ferreira | Fernando de Carvalho da Silva | Luana da Silva Magalhães Forezi | Vanessa Nascimento
Source: Pharmaceuticals (article, 2025-05-26)
Field: Chemistry — Organic Chemistry

Design, Synthesis, and In Vitro Evaluation of 4-(Arylchalcogenyl)methyl)-1H-1,2,3-triazol-1-yl-menadione: Exploring Their Potential Against Tuberculosis <b>Background/Objectives:</b> In this study, a novel series of 4-(arylchalcogenyl)methyl)-1H-1,2,3-Triazol-1-yl-menadione derivatives were synthesized to explore their potential as new antituberculosis (anti-TB) agents. Selenium-containing compounds are known for their significant antimycobacterial activity, which motivated their inclusion in the design. <b>Methods:</b> The target compounds were synthesized via a copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, affording yields ranging from 34% to 93%. All compounds were evaluated in vitro for anti-TB activity against <i>Mycobacterium tuberculosis</i> H37Rv (ATCC 27294), as well as a drug-resistant strain (T113/09). <b>Results:</b> Several selenium-containing derivatives exhibited promising activity. Compounds <b>9b</b> and <b>9g</b> were equipotent to the first-line anti-TB drug, and one compound surpassed its activity. Notably, compounds <b>9a</b>, <b>9b</b>, <b>9g</b>, and <b>9h</b> also showed efficacy against the INH- and RIF-resistant <i>Mtb</i> strain T113/09. <b>Conclusions:</b> The efficacy of selenium-containing triazole-menadione hybrids against both sensitive and resistant <i>Mtb</i> strains highlight their potential as candidates for addressing antimicrobial resistance in TB treatment. Further investigations are required to understand their mechanisms of action and assess their in vivo therapeutic potential.. Menadione ; Antimycobacterial ; Mycobacterium tuberculosis ; Antimicrobial ; Click chemistry ; Extensively drug-resistant tuberculosis ; In vitro ; Chemistry ; In vivo ; Cycloaddition ; Selenium ; Drug resistance ; Combinatorial chemistry ; Tuberculosis ; Microbiology ; Biology ; Medicine ; Biochemistry ; Organic chemistry ; Enzyme ; Catalysis ; Biotechnology Click Chemistry and Applications ; Biochemical and Molecular Research ; Synthesis and Biological Evaluation
Authors: Alejandra Rubio Hernández‐Sampelayo | Laura Diñeiro | Dulce María González-García | Enrique Martínez‐Campos | Rodrigo Navarro | Ángel Marcos‐Fernández
Source: Polymers (article, 2025-06-17)
Field: Materials Science — Biomaterials

Biodegradable Polyurethanes for Tissue Engineering: Influence of L-Lactide Content on Degradation and Mechanical Properties The influence of L-lactide content (between 15% and 43%) on the degradation of biodegradable polyurethanes (PUs) for tissue engineering was systematically addressed in this study. An ideal tissue scaffold should exhibit a mechanical response and degradability appropriate for the host tissue. To achieve it, polyols containing ε-caprolactone and L-lactide moieties were used, with the random distribution of lactide units disrupting the regularity, and hence the crystallinity, of poly(caprolactone) segments, facilitating their degradation. The biodegradable PUs were synthesised using these copolymers as soft segments and were characterised through various physicochemical techniques, including bioassays and water absorption measurements. It was determined that mechanical behaviour and water absorption depended significantly on molecular weight, L-lactide content in the soft segment, and the crystallinity of the hard segment. Additionally, two types of chain extenders were also evaluated: hydrolysable and non-hydrolysable. PUs based on hydrolysable chain extenders achieved higher molecular weights and exhibited better mechanical performance than their non-hydrolysable counterparts. To assess the cytocompatibility of these materials, an endothelial model was used, involving metabolic activity and DNA content analysis. The results demonstrated good cell adhesion and the absence of toxicity, confirming the viability of cell growth on the surfaces of these biodegradable PUs. The PUs developed in this study exhibited a low initial modulus and adjustable mechanical properties, highlighting their potential application in tissue engineering as biodegradable and biocompatible biomedical materials. Crystallinity ; Lactide ; Biodegradation ; Tissue engineering ; Polyester ; Caprolactone ; Biodegradable polymer ; Materials science ; Absorption of water ; Degradation (telecommunications) ; Polyurethane ; Chemical engineering ; Copolymer ; Polymer chemistry ; Chemistry ; Polymer ; Biomedical engineering ; Composite material ; Organic chemistry Electrospun Nanofibers in Biomedical Applications ; biodegradable polymer synthesis and properties ; Polymer composites and self-healing
Authors: M. Borah
Source: Journal of Nanoscience and Technology (article, 2025-04-21)
Field: Materials Science — Materials Chemistry

Theoretical Insights into Growth Mechanisms of ZnO Nanorods Zinc oxide (ZnO) nanorods exhibit unique anisotropic growth behaviour influenced by surface energy variations, chemical potential gradients, and synthesis conditions. This study explores the fundamental thermodynamic and kinetic factors governing ZnO nanorod formation, focusing on surface energy minimization, Gibbs free energy stability, and Wulff construction-based morphology prediction. The role of chemical potential, supersaturation, and Ostwald ripening in directing anisotropic growth along the c-axis is also analyzed. Additionally, the hydrothermal synthesis of ZnO nanorods, the most often used synthesis process has also been used an example for understanding the whole ZnO nanorod formation process, highlighting the impact of reaction parameters such as temperature, pH, precursor concentration, and surfactant-mediated morphology control. Nanorod ; Materials science ; Nanotechnology ZnO doping and properties ; Gas Sensing Nanomaterials and Sensors ; Copper-based nanomaterials and applications
Authors: Siming Li | Jieyu Zhang | Suizhu Pei | Kangjia Wu | Bowen Zhao | Min Wang | Yawei Li
Source: Nano Research (article, 2025-08-04)
Field: Materials Science — Materials Chemistry

Surface diffusion-limited dealloying: A strategy for porosity construction in small-sized alloy nanoparticle electrocatalysts The formation of porosity within nanoparticles via dealloying is notably constrained by the dimensions of the precursor particles, a limitation stemming from the surface kinetic processes occurring during dealloying. In this study, we present a straightforward methodology, specifically tailored for fabricating diminutive nanoporous alloy nanoparticles, originating from their small-sized precursor counterparts. We initiated our research with precursor PtNi alloy nanoparticles which possess an average diameter of 9 nm. By incorporating an extrinsic metal, Ir, known for its slower surface diffusion on the nanoparticle surface, we successfully modulated the surface migration velocity of Pt during the dealloying process of the PtNi alloy nanoparticles. This precise manipulation led to the formation of an abundantly complex nanoporous structure on diminutive PtNi nanoparticles. Owing to their enhanced high surface area-to-volume ratio and the synergistic alloy effect, electrochemical tests revealed that the Ir-coated diminutive nanoporous PtNi nanoparticles exhibit superior electrocatalytic activities towards oxygen reduction and formic acid oxidation reactions. Furthermore, the presence of Ir on the surface effectively suppresses the surface diffusion rate of Pt, thereby significantly inhibiting the coarsening evolution of the porous metallic structure. This intervention ensures the long-term preservation of both structural integrity and catalytic stability. Porosity ; Alloy ; Materials science ; Nanoparticle ; Nanotechnology ; Diffusion ; Metallurgy ; Chemical engineering ; Composite material ; Engineering Nanoporous metals and alloys ; Electrocatalysts for Energy Conversion ; Nanomaterials for catalytic reactions
Authors: Apoorv Parikh | Nader Mahinpey
Source: ChemCatChem (article, 2025-10-03)
Field: Chemistry — Inorganic Chemistry

Optimizing Zeolite 13X Synthesis from Kaolin Clay for Higher CO <sub>2</sub> Adsorption: A Statistical Approach Abstract Zeolite 13X is a promising material for CO 2 capture due to its high adsorption kinetics and capacity. However, limited studies systematically evaluate the effect of synthesis parameters on performance. This study uses a design of experiments (DoE) approach to examine the influence of silica‐to‐alumina ratio, aging time, crystallization time, and temperature on CO 2 uptake. Kaolin, a low‐cost natural clay, served as the raw material. Synthesis conditions were selected based on extreme values reported in literature to cover a broad range. The resulting zeolite 13X showed up to three times higher CO 2 adsorption capacity than previously reported for kaolin‐derived variants. Characterization via XRD, CO 2 /N 2 isotherms, and SEM confirmed structural integrity and performance. Among variables, crystallization temperature had the strongest positive effect, with others influencing within specific ranges. Statistical modeling identified the linear model as significant (R 2 = 0.76, p = 1.43 × 10 −5 ), while the cubic model achieved the best fit (p = 0.014). Model selection was further refined using additional statistical metrics. Optimal conditions yielded a CO 2 adsorption capacity of 4.7 ± 0.3 mmol/g at atmospheric pressure and 30 °C temperature. These results emphasize the need for careful synthesis optimization to enhance the carbon capture performance of zeolite 13X. Zeolite ; Adsorption ; Crystallization ; Raw material ; Kinetics ; Characterization (materials science) Zeolite Catalysis and Synthesis ; Carbon Dioxide Capture Technologies ; Membrane Separation and Gas Transport
Authors: Chirag Apte | Nicholas W. Heller | Ben Zhen Huang | Adam Marr | Kjell Jorner | Alán Aspuru‐Guzik | Andrei K. Yudin
Source: Chemical Science (article, 2025-01-01)
Field: Chemistry — Organic Chemistry

A borindolizine platform for the design of fluorophores with tunable emissions Here we describe the design and applications of borindolizine, a novel scaffold with broadly tunable fluorescence and a high Stokes shift. Two classes of emitters were synthesized through rational scaffold modification, resulting in blue-emitting carboxyborindolizines (<i>λ</i> <sub>max,em</sub> = 431-459 nm) and green-emitting aryl borindolizines (<i>λ</i> <sub>max,em</sub> = 489-519 nm). Experimental structure-emission trends were used to validate a computational spectral prediction model and to subsequently design a red-emissive borindolizine scaffold. The red-emissive isoquinolyl borinidolizine was prepared, and the experimental emission (<i>λ</i> <sub>max,abs</sub> = 370 nm, <i>λ</i> <sub>max,em</sub> = 635 nm) was in excellent agreement with the theoretical emission (<i>λ</i> <sub>max,em</sub> = 646 nm). These results show how the application of data science can produce fluorophores with desirable spectroscopic properties through the borindolizine scaffold. Rational design ; Fluorescence ; Scaffold ; Spectral properties ; Aryl ; Power (physics) Synthesis and Reactivity of Heterocycles ; Synthesis and Properties of Aromatic Compounds ; Organoboron and organosilicon chemistry
Authors: M. M. Atta | Israa Al‐Ani | Ibrahim Al‐Deeb | Khaldun M. AlAzzam | Tha’er Ata | Mohammad A. Almullah | Enas Daoud | Feras Darwish Elhajji
Source: Pharmaceutics (article, 2025-07-28)
Field: Materials Science — Polymers and Plastics

In Vitro and In Vivo Evaluation of Alectinib-Loaded Dendrimer Nanoparticles as a Drug Delivery System for Non-Small Cell Lung Carcinoma <b>Background/Objectives</b>: Alectinib, a second-generation tyrosine kinase inhibitor indicated for the treatment of non-small-cell lung cancer (NSCLC), exhibits suboptimal oral bioavailability, primarily attributable to its inherently low aqueous solubility and limited dissolution kinetics. This study aimed to enhance Alectinib's solubility and therapeutic efficacy by formulating a G4-NH2-PAMAM dendrimer complex. <b>Methods</b>: The complex was prepared using the organic solvent evaporation method and characterized by DSC, FTIR, dynamic light scattering (DLS), and zeta potential measurements. A validated high-performance liquid chromatography (HPLC) method quantified the Alectinib. In vitro drug release studies compared free Alectinib with the G4-NH2-PAMAM dendrimer complex. Cytotoxicity against NSCLC cell line A549 was assessed using MTT assays, clonogenic assay, and scratch-wound assay. Xenograft effect was investigated in the H460 lung cell line. Pharmacokinetic parameters were evaluated in rats using LC-MS/MS. <b>Results</b>: Alectinib exhibited an encapsulation efficiency of 59 ± 5%. In vitro release studies demonstrated sustained drug release at pH 6.8 and faster degradation at pH 2.5. Anticancer activity in vitro showed comparable efficacy to free Alectinib, with 98% migration inhibition. In vivo tumor suppression studies revealed near-complete tumor regression (~100%) after 17 days of treatment, compared to 75% with free Alectinib. Pharmacokinetic analysis indicated enhanced absorption (shorter Tmax), prolonged systemic circulation (longer half-life), and higher bioavailability (increased AUC) for the dendrimer-complexed drug. <b>Conclusions</b>: These findings suggest that the G4-NH2-PAMAM dendrimer system significantly improves Alectinib's pharmacokinetics and therapeutic potential, making it a promising approach for NSCLC treatment. Alectinib ; Chemistry ; Pharmacokinetics ; Bioavailability ; In vivo ; Erlotinib ; Dendrimer ; Pharmacology ; Drug delivery ; Lung cancer ; Medicine ; Biochemistry ; Anaplastic lymphoma kinase ; Oncology ; Organic chemistry ; Receptor ; Epidermal growth factor receptor Dendrimers and Hyperbranched Polymers ; Quinazolinone synthesis and applications ; Chemical Synthesis and Analysis
Authors: Katerina Gavriel | Daniel Deißenbeck | Thomas J. Rutjes | Daniëlle W. T. Geers | Jan Meisner | Kevin Neumann
Source: ChemistryEurope (article, 2025-08-08)
Field: Chemistry — Organic Chemistry

Programmable Site‐Selectivity: pH‐Modulated Triazine–Thiol Exchange for Site‐ and Chemoselective Cysteine Labeling The chemical modification of peptides is a powerful method to enhance their pharmacological properties, including membrane permeability, metabolic stability, and binding affinity. Over recent decades, advances in chemoselective modifications have enabled the construction of well‐defined peptide scaffolds with uniform and precise molecular architectures. However, beyond chemoselectivity, achieving true site‐selectivity by differentiating between identical amino acids at distinct positions within complex peptide scaffolds remains a key challenge. So far, site‐selectivity of cysteine labeling has been largely restricted to N ‐terminal cysteines. Herein, a programmable strategy for site‐selective cysteine modifications is reported, ultimately enabling precise control over the location of cysteine functionalization within peptides. This is accomplished by employing a triazine–thiol exchange, a dynamic covalent reaction with pH‐adjustable site‐selectivity. It is shown that under acidic conditions internal cysteines are modified while preserving the N ‐terminal cysteine functionality. Conversely, at neutral pH, site‐selective modification of N ‐terminal cysteines is achieved. The modification of N ‐terminal cysteines using triazine–thiol exchange proceeds via an S–N shift, which converts the dynamic linkage into an irreversible modification. Density functional theory computations reveal that the site‐selectivity originates from modulation of the formed intermediate, providing insights for future mechanism‐based designs of site‐selective peptide chemistries. The here presented methodology allows chemists to gain control over site‐selectivity and unlock new possibilities for precision peptide engineering. Cysteine ; Thiol ; Chemistry ; Selectivity ; Triazine ; Active site ; 1,3,5-Triazine ; Combinatorial chemistry ; Biochemistry ; Organic chemistry ; Catalysis Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Adenosine and Purinergic Signaling
Authors: Sriram Sundaresan | Julian Eppelsheimer | Luca M. Carrella | Eva Rentschler
Source: European Journal of Inorganic Chemistry (article, 2025-02-04)
Field: Materials Science — Electronic, Optical and Magnetic Materials

A Hobson's Choice Co‐Ligand in Imparting Spin Crossover in Fe(II) Complexes Based on 1,3,4‐Oxadiazole Ligands Abstract In this manuscript we report the synthesis of three methanol solvatomorphs of Fe(II) complexes with the 2‐(2‐phenyl)‐5‐[N,N‐bis(2‐pyridylmethyl)aminomethyl]‐1,3,4‐oxadiazole ( L Ph−ODA ) ligand and three different NCE co‐ligands where E=S, Se and BH 3 ( C1 – C3 ). The complexes obtained were characterized by single crystal X‐ray crystallography and SQUID magnetometry between 2 and 300 K. Complexes C1 and C2 remain in the high spin state over the entire measured temperature window, whereas complex C3 exhibits a solvent dependent spin transition with a T 1/2 of 166 K. Upon heating the sample to 400 K and removing methanol, the complex exhibited a two‐step spin transition with the first step having a T 1/2 of 215 K and a second step having a T 1/2 of 137 K. Chemistry ; Spin crossover ; Ligand (biochemistry) ; Spin transition ; Crystallography ; Oxadiazole ; Methanol ; Spin states ; Solvent ; Spin (aerodynamics) ; Single crystal ; Stereochemistry ; Inorganic chemistry ; Organic chemistry Magnetism in coordination complexes ; Metal complexes synthesis and properties ; Metal-Catalyzed Oxygenation Mechanisms
Authors: Hui Guo | Wei‐Quan Lin | Ji‐Dong Leng
Source: Molecules (article, 2025-05-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Field-Induced Slow Magnetic Relaxation in Pentacoordinate Co(II) Complexes: Tuning Magnetic Anisotropy Through Halide Substitution We report the synthesis, structural characterization, and magnetic properties of three pentacoordinate Co(II) complexes [CoX(dppb)<sub>2</sub>]X (X = Cl (<b>1Cl</b>), Br (<b>2Br</b>), and I (<b>3I</b>)) supported by the bidentate phosphine ligand 1,2-bis(diphenylphosphino)benzene (dppb). Single-crystal X-ray diffraction reveals that all three complexes adopt similar vacant octahedron (<i>C</i><sub>4v</sub>) geometries with the halide ligand in one axial position. Magnetic studies demonstrate that these complexes exhibit field-induced slow magnetic relaxation behaviors, with positive <i>D</i> values of 25.3(2), 21.6(1), and 19.4(2) cm<sup>-1</sup> for <b>1Cl</b>, <b>2Br</b>, and <b>3I</b>, respectively. Detailed analysis of the relaxation dynamics reveals that Raman processes dominate at higher temperatures, with systematic variations in relaxation parameters across the series. The systematic variations in magnetic anisotropy and slow magnetic relaxation behaviors of the three complexes correlate with the decreasing electronegativity of the halide ligands. Halide ; Anisotropy ; Magnetic anisotropy ; Substitution (logic) ; Condensed matter physics ; Relaxation (psychology) ; Magnetic field ; Chemistry ; Chemical physics ; Materials science ; Magnetic relaxation ; Magnetization ; Inorganic chemistry ; Physics ; Optics ; Quantum mechanics Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Advanced NMR Techniques and Applications
Authors: Keerthi Pilakka | Jawahar I. Naseemabeevi | Subodh Ganesanpotti
Source: Polymer Engineering and Science (article, 2025-12-16)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Conductive Carbon Black Reinforced Room Temperature Vulcanizing Silicone Rubber Composites: Tunable Negative Permittivity, Enhanced <scp>EMI</scp> Shielding and Photothermal Conversion Properties ABSTRACT Light‐weight and flexible electromagnetic interference (EMI) shields can endure repeated bending and stretching without compromising their integrity and effectiveness. In this work, light‐weight, flexible, and free‐standing room‐temperature vulcanizing silicone rubber (RTV SR) composites, incorporated with conductive carbon black (CCB) of varying concentrations (0 to 15 wt%), were fabricated via a simple solution casting method. The spectroscopic analysis confirms the complete curing of RTV SR and the successful integration of CCB. The 3D conducting networks and the hopping electrons govern the electrical conductivity of the composites. A percolation‐triggered negative permittivity was observed in the composites containing 10–15 wt% of CCB and induced a capacitance‐to‐inductance transition. The combined effect of dipolar resonance and low‐frequency plasmonic state is responsible for the observed negative permittivity, and the transition frequency can be tuned according to the filler concentration. The present work reports an average EMI shielding effectiveness (EMI SE) of 25.2 dB in the Ku and K bands (12.4 to 26.5 GHz) of the microwave region, corresponding to 99.997% of the EM energy attenuation for a thickness of only 1.4 mm within the 15% CCB loading. In‐depth analysis of the dielectric properties in the composite reveals that the mitigation of EM energy in CCB/RTV SR composites is demonstrated by the combined effect of conduction losses and diverse polarization relaxations arising from interfaces, micro‐capacitors formed by the CCB and RTV SR matrix, etc. The flexibility, and water‐resistant nature, in addition to photothermal conversion capabilities, makes CCB RTV‐15 a compatible EMI shield in modern electronics and thermal management systems. Electromagnetic shielding ; Carbon black ; Vulcanization ; Electrical conductor ; Silicone rubber ; Dielectric ; Composite number ; Microwave ; Permittivity Electromagnetic wave absorption materials ; Smart Materials for Construction ; Advanced Antenna and Metasurface Technologies