jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ricardo Silva-Carvalho | Daniela Martins | Tarsila G. Castro | Ana Cristina Rodrigues | Bruna Costa | Paula Parreira | Artur Cavaco‐Paulo | Fernando Dourado | M. Cristina L. Martins | Miguel Gama
Source: Food Hydrocolloids (article, 2025-11-07)
Field: Materials Science — Biomaterials

Polysaccharide-mediated stabilization of bacterial nanocellulose dispersions: Experimental and molecular dynamics study Colloidal dispersions of pristine cellulose (nano- or microsized; fibrillar or particulate), are typically unstable in water due to interfiber/interparticle interactions. Carboxymethyl cellulose (CMC) is known to effectively stabilize these dispersions, allowing for full recovery of the properties upon redispersion after drying. However, the underlying mechanism has been unclear. This study investigated why CMC effectively stabilized cellulose and whether other polysaccharides could perform similarly. Mixtures of bacterial nanocellulose (BNC) with chia mucilage (ChM), hyaluronic acid (HA), pectin (Pec), xanthan gum (XG), locust bean gum (LBG), salep, alginate (Alg), and polyol glycerol (Gly) were compared to mixtures of BNC:CMC. The stability and redispersibility after drying of each mixture were analyzed. Only ChM produced homogeneous and stable BNC dispersions similar to CMC. The polysaccharides’ adsorption onto cellulose films was studied using quartz crystal microbalance with dissipation (QCM-D). CMC and ChM showed stronger and more stable adsorption, with higher retained mass after washing (10.0 ± 0.3 and 7.8 ± 2.3 mg/m 2 , respectively), compared to Alg, HA, or XG (3.6 ± 0.6, 1.0 ± 0.3 and 0.2 ± 0.1mg/m 2 , respectively). Molecular dynamics simulations confirmed the stronger interactions of CMC and ChM with cellulose surfaces, characterized by hydrogen bonding and perpendicular orientation. • ChM was identified as a natural alternative to CMC for BC stabilization • Other polysaccharides tested for co-drying failed to stabilize BC dispersions • CMC and ChM show strong, stable adsorption on cellulose thin films • CMC and ChM are predicted to bind cellulose in a perpendicular orientation • ChM enables clean-label, bio-based BC formulations for food and cosmetics Nanocellulose ; Cellulose ; Carboxymethyl cellulose ; Locust bean gum ; Bacterial cellulose ; Polysaccharide ; Xanthan gum ; Biopolymer ; Adsorption Advanced Cellulose Research Studies ; Polysaccharides and Plant Cell Walls ; Nanocomposite Films for Food Packaging
Authors: Edyta Hebda | Kazimierz Wróbel | Aleksandra Cieślik | Kinga Szołdrowska | Jan Ozimek | Paulina Zając | Konstantinos N. Raftopoulos | Krzysztof Pielichowski
Source: Preprints.org (preprint, 2025-06-20)
Field: Materials Science — Polymers and Plastics

Structurally Ordered NIPUs via Catalyst-Free Synthesis with Hard Segments Based on Erythritol and a Long-Chain Diamine A series of linear isocyanate-free polyurethanes (NIPUs) were obtained by aminolysis of erythritol dicarbonate (EDC) with polyethers (diamino-PEG, diamino-PPO and diamino-PEG/PPO) and 1,12-diaminododecane (DADD), which acts as a chain extender to form hard segments. The obtained NIPUs contained different concentrations of DADD relative to the polyether (72.5–80 wt%). Detailed chemical structure analysis of synthesized NIPU was performed using a combination of FTIR and 1H NMR. FTIR spectra confirmed that the EDC-DADD segments formed a network of hydrogen bonds. This is reflected in WAXD diffractograms showing ordered crystalline domains originating in DADD. The reflections assigned to the DADD segments exhibited changes in their position and intensity with decreasing concentration, indicating an increase in interplanar spacing and a loss of higher-order order. WAXD also showed that the soft segments of PEG and PEG/PPO retain their ordered crystal structure regardless of the DADD content. At a larger length scale, SAXS revealed similar micromorphology for the different polyethers, with a broad peak indicating long-range order in the DADD-rich segments and a weak separation of the soft and hard phases. DSC analyses confirmed the complex phase behavior, where the PEG-based materials showed melting of crystalline fragments and the amorphous PPO showed a glass transition. DMA indicated the stability of the glass transition temperature in the PPO samples and the presence of an unusual structural transition. The results emphasize the influence of the type of poly(ether) on the thermal and microphase properties of the studied non-isocyanate polyurethanes. Glass transition ; Materials science ; Diamine ; Crystallinity ; PEG ratio ; Fourier transform infrared spectroscopy ; Crystallography ; Polymer chemistry ; Ether ; Chemical engineering ; Polymer ; Chemistry ; Organic chemistry ; Composite material Polymer composites and self-healing ; Antimicrobial agents and applications
Authors: Agata Tyszka‐Gumkowska | Mateusz Brzeziński | Sylwester Gawinkowski | Tomasz Polczyk | Wojciech Wegner | Mateusz Wlazło | Piotr Bernatowicz | Jan Nawrocki | Przemysław Gaweł | Krzysztof Noworyta | Jakub Ostapko
Source: Chemistry of Materials (article, 2025-10-01)
Field: Materials Science — Materials Chemistry

Reductive Transformation of Imine Covalent Organic Frameworks into Emissive Polymers: Insights into Emission Quenching Although imine-linked covalent organic frameworks (COFs) are readily synthesized, their lack of intrinsic emission constrains their potential in optoelectronic applications. Moreover, the underlying mechanisms governing excited-state energy dissipation remain poorly understood. To overcome these limitations, we present a straightforward strategy to transform nonemissive, anthracene-based imine-COFs (<b>im-COF</b>) into highly emissive amine-based covalent organic polymers (<b>am-COP</b>) through NaBH<sub>3</sub>CN/benzoic acid reduction, achieving solid-state emission quantum yields of up to 30%. To clarify the excited-state energy dissipation mechanisms in COFs and COPs, we synthesized molecular reference compounds featuring either imine or amine functionalities. Photophysical studies, supported by density functional theory (DFT) calculations, reveal that the excited states of both amines and imines exhibit weak charge transfer (CT) properties. Furthermore, a comparative analysis of the photophysical behavior of molecular references, <b>im-COFs</b>, and <b>am-COPs</b> demonstrates that the polymer emission arising from charge-transfer processes is modulated by the polymer's intrinsic polarity. These findings provide fundamental insights into the photophysical behavior of COFs, thus paving the way for the development of emissive porous materials with promising advanced applications. Imine ; Covalent bond ; Density functional theory ; Quenching (fluorescence) ; Polymer ; Excited state ; Amine gas treating ; Aggregation-induced emission Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Luminescence and Fluorescent Materials
Authors: Alen Sam Thomas | Philip Nathaniel Immanuel | Neena Prasad | Achiad Goldreich | Jonathan Prilusky | Lena Yadgarov
Source: ChemRxiv (preprint, 2025-02-18)
Field: Chemistry — Inorganic Chemistry

Synthesis of CsPbBr₃ Decorated ZIF-8 Nanocomposite for Enhanced Photocatalytic Performance CsPbBr₃ (CPB) perovskite nanocrystals (NCs) have attracted considerable interest due to their outstanding charge carrier mobility, long diffusion lengths, and efficient visible light absorption, making them ideal candidates for photocatalysis, light-emitting diodes (LEDs), solar cells, and photodetectors. However, their practical applications are limited by poor environmental stability. We employed a metal-organic framework (MOF) to address this challenge as a stabilizing matrix, selecting ZIF-8 for its exceptional thermal and chemical stability, high surface area, and versatile synthesis routes. The CPB/ZIF-8 nanocomposite was synthesized by integrating hot-injection-produced CPB nanocrystals with ZIF-8 using an optimized mixing approach, ensuring a uniform NCs distribution. Electron microscopy (EM) analysis confirmed the well-controlled and uniform distribution of the NCs on the surface of the ZIF-8. Moreover, the Fourier-transform infrared spectroscopy (FTIR) revealed ligand exchange, where the imidazole linkers of the ZIF-8 structure replace the NCs ligands. The process promotes almost epitaxial attachment of the latter, thus promoting effective charge interactions in the integration process. The unshifted absorbance spectra verified the preservation of optical activity, whereas a 92% quenching in photoluminescence (PL) indicated efficient charge separation and reduced electron-hole recombination. To investigate charge transfer mechanisms, photocatalytic dye degradation under visible light irradiation was employed using methyl orange (MO) and bromocresol green (BCG) as model dyes. The CPB/ZIF-8 nanocomposite exhibited significantly enhanced photocatalytic performance, achieving 1.48 and 1.75 times higher degradation rates for MO and BCG, respectively, compared to pristine CPB NCs. Electron paramagnetic resonance (EPR) studies demonstrated superior radical generation capabilities, particularly hydroxyl radicals (•OH), further confirming enhanced charge transfer and photocatalytic efficiency. These findings underscore the synergistic interaction between CPB NCs and ZIF-8, positioning the CPB/ZIF-8 nanocomposite as a promising material for photocatalysis and optoelectronic applications. Photocatalysis ; Nanocomposite ; Materials science ; Chemical engineering ; Nanotechnology ; Chemistry ; Catalysis Metal-Organic Frameworks: Synthesis and Applications
Authors: Idris A. Yakubu | Elele U. Ugoeze | John Tsado Mathew
Source: Science World Journal (article, 2025-02-14)
Field: Chemistry — Inorganic Chemistry

Preparation and characterization of MoO&lt;sub&gt;3&lt;/sub&gt; nanoparticles for the photocatalytic degradation of dyeing wastewater This study focuses on the preparation and characterization of MoO₃ nanoparticles for the photocatalytic degradation of dyeing wastewater. The XRD pattern of MoO₃ shows distinct peaks at 2θ values of 12.8°, 23.4°, 25.7°, 27.3°, and 39.0°, corresponding to specific crystal planes and confirming its α-MoO₃ phase, validated against JCPDS card number 05-0508. The morphology reveals stacked or crumpled particles with a high surface area conducive to catalytic activities. EDX analysis identifies molybdenum (Mo) and oxygen (O) with characteristic peaks at 2.29 keV (Mo Lα), 17.48 keV (Mo Kα), 19.63 keV (Mo Kβ), and 0.52 keV (O Kα), confirming the material's composition. MoO₃’s layered structure, influenced by van der Waals forces, offers unique interlayer spacing advantageous for photocatalytic processes. Photodegradation experiments showed progressive efficiency: at 10 minutes, MoO₃ achieved 8.58%; by 40 minutes, it increased to 30.42%, and at 50 minutes, reached 42.3%. Efficiency peaked at 60 minutes with 50.52%, progressing to 60.8% at 70 minutes and 71.03% at 90 minutes, finally achieving 75.25% at 100 minutes. These results demonstrate MoO₃ nanoparticles' effectiveness in degrading dye pollutants, highlighting their potential for sustainable wastewater treatment applications. Photocatalysis ; Dyeing ; Degradation (telecommunications) ; Characterization (materials science) ; Wastewater ; Nuclear chemistry ; Nanoparticle ; Materials science ; Chemical engineering ; Chemistry ; Nanotechnology ; Waste management ; Organic chemistry ; Catalysis ; Computer science ; Engineering ; Composite material ; Telecommunications Pigment Synthesis and Properties ; Water and Wastewater Treatment ; TiO2 Photocatalysis and Solar Cells
Authors: Dong Xing | Peng Xue | Yong-Jia CHEN | Zhenju Jiang | Wei Li | Chen Jiu-jun | Yong Xiang | Zhouyu Wang | Qiao Song
Source: ChemCatChem (article, 2025-05-27)
Field: Chemistry — Organic Chemistry

Selective Oxidation of Benzyl and Allyl Alcohols to Carbonyl Compounds or Acids Mediated by Iron Photocatalysts Abstract This study presents a selective oxidation method for benzyl and allyl alcohols to aldehydes, ketones, or carboxylic acids using inexpensive iron salts as photocatalysts and molecular oxygen (air) as the sole oxidant under mild conditions. The process demonstrates high selectivity for the hydroxyl groups of benzyl and allyl alcohols, while minimizing the reactivity of other functional groups, thereby enhancing atom efficiency. The scalability and industrial applicability of the method are evidenced by its successful use in the modification of natural products and the synthesis of pharmaceutical intermediates, as well as through scale‐up experiments, continuous‐flow processes, and the successful implementation of tandem reactions. Mechanistic studies suggest that the reaction proceeds via a radical pathway, mediated by singlet oxygen and superoxide anions. Chemistry ; Organic chemistry ; Alcohol oxidation ; Photocatalysis ; Catalysis Oxidative Organic Chemistry Reactions ; Chemical Synthesis and Reactions ; Mesoporous Materials and Catalysis
Authors: M. Dehghanipour | Anjan Kumar | Prakash Kanjariya | M. Manjula | Rishiv Kalia | Shaker Al-Hasnaawei | D. S. Jayalakshmi | Apurav Gautam | Gurumurthy B. Ramaiah
Source: Scientific Reports (article, 2025-09-26)
Field: Materials Science — Materials Chemistry

A computational dive into tuning nitrosourea adsorption on T-graphene nanosheets This study examines the adsorption of a nitrosourea (NU) drug molecule onto pristine and doped T-graphene (TG) nanosheets, specifically those doped with boron (BTG) and aluminum (AlTG), utilizing density functional theory (DFT) at the M06-2X/6-31 + G(d,p) level of theory. We investigated the geometric, electronic, and energetic properties of the resulting complexes, focusing on adsorption energies, HOMO-LUMO gaps (E<sub>g</sub>), molecular electrostatic potential (MEP), natural bond orbital (NBO) analysis, and quantum theory of atoms in molecules (QTAIM). Our findings indicate that aluminum doping significantly enhances the adsorption of NU onto the TG nanosheet, exhibiting strong chemisorption as evidenced by a high adsorption energy (E<sub>ads</sub>) of - 41.46 kcal mol<sup>-1</sup> and substantial charge transfer. However, this high adsorption energy results in a very lengthy desorption time of 2.3 × 10<sup>18</sup> s. In contrast, boron doping increases the E<sub>ads</sub> to a more manageable level (- 14.91 kcal mol<sup>-1</sup>), leading to a recovery time of 8.3 × 10<sup>-2</sup> s, which is advantageous from a drug delivery perspective. Frontier molecular orbitals analysis revealed that the most prominent E<sub>g</sub> change upon adsorption of NU occurs in the case of BTG with a 10.46% reduction. While the variations of E<sub>g</sub> for TG-NU and AlTG-NU are - 1.31% and 5.20%, respectively. NBO analysis confirmed substantial donor-acceptor interactions in the AlTG-NU complex, while QTAIM indicated the presence of partially covalent interactions. Pristine TG and BTG exhibited weaker interactions with NU; however, the bonding nature remained partially covalent in both cases. The calculated recovery times further suggest that BTG provides a more favorable drug release profile compared to TG and AlTG. This study highlights the potential of boron-doped TG as an effective nanocarrier for drug delivery, underscoring the essential role of doping in tailoring the electronic and adsorption properties of graphene-based materials. Adsorption ; Natural bond orbital ; Covalent bond ; Chemisorption ; Density functional theory ; Boron ; Molecule ; Desorption Graphene research and applications ; Graphene and Nanomaterials Applications ; Boron and Carbon Nanomaterials Research
Authors: Órla Conboy | Emily Q. Rushworth | Christopher J. Taylor | Colin Levy | Mary Ortmayer | George F. S. Whitehead | Andy Yen | Ciro Romano | Anthony P. Green | David J. Procter
Source: Journal of the American Chemical Society (article, 2025-11-04)
Field: Chemistry — Organic Chemistry

Biocatalytic Activation of Sulfur Heteroaromatics Facilitates Dearomatizing Cross-Couplings to Set Stereogenic Centers or Axes The enantioselective manipulation of abundant flat (hetero)aromatic building blocks through either dearomatization, to establish new stereocenters, or cross-coupling, to construct a stereogenic axis, is an attractive means to generate three-dimensional molecular architectures. By merging the selectivity of engineered biocatalysts with the versatility of chemical synthesis, we establish a new platform for the metal-free enantioselective manipulation of sulfur-containing heteroaromatics, allowing either point or axial chirality to be set. The key to this approach is our ability to leverage the prochirality of sulfur heteroarenes; biocatalytic oxidation of benzothiophenes "switches on" reactivity and establishes a sulfur stereocenter that directs the stereochemical course of subsequent cross-couplings with non-prefunctionalized partners. Exploiting a previously unexplored mechanism, either point-to-point or point-to-axial chirality transfer from sulfur selectively delivers two different sets of chiral molecules. Enzyme evolution is used to convert a wild-type oxygenase into an efficient and selective engineered <i>S</i>-oxygenase capable of furnishing enantiopure benzothiophene <i>S</i>-oxides─little-known sulfoxides whose configurational stability we map out. Our integrated chemoenzymatic approach provides a blueprint for unlocking the potential of sulfur chirality, lying dormant in important heterocycles, to direct transformations that deliver diverse enantioenriched products. Stereocenter ; Enantiopure drug ; Enantioselective synthesis ; Chirality (physics) ; Benzothiophene ; Axial chirality ; Sulfur ; Atropisomer Axial and Atropisomeric Chirality Synthesis ; Cyclopropane Reaction Mechanisms ; Surface Chemistry and Catalysis
Authors: Mary C. Jones | Leide P. Cavalcanti | Gregory N. Smith | Robert M. Dalgliesh | Stephen R. Euston | Filipe Vilela | Valeria Arrighi | Gareth O. Lloyd
Source: Communications Chemistry (article, 2025-08-28)
Field: Materials Science — Biomaterials

Self-sorting and co-assembly control in multicomponent supramolecular hydrogels with dual monomer and polymer statistical distribution Multicomponent supramolecular polymer gels are a class of soft matter materials which form via the assembly of two or more small molecules. Different structures can be generated with interesting potential functions and applications. Insight into the assembly mechanism is key in the design of these systems for specific applications. Herein, a series of hydrogels with diverse structures and functionalities were synthesised. Using dynamic covalent chemistry as a key tool we show that it is possible to control the monomer assembly, forming both self-sorted and co-assembled polymers and gels from the same initial components. The hierarchical structure of the gels is difficult to elucidate. We emphasise the significance of small-angle neutron scattering (SANS) and spin-echo SANS (SESANS) measurements in characterising these intricate assemblies and demonstrate that these techniques are able to differentiate among self-sorted and co-assembled structures even when using chemically similar components. Self-healing hydrogels ; Supramolecular polymers ; Dual (grammatical number) ; Polymer ; Sorting ; Monomer ; Supramolecular chemistry ; Distribution (mathematics) ; Materials science ; Polymer science ; Chemical engineering ; Nanotechnology ; Polymer chemistry ; Computer science ; Chemistry ; Mathematics ; Crystallography ; Composite material ; Engineering ; Art ; Algorithm Supramolecular Self-Assembly in Materials ; Polydiacetylene-based materials and applications ; Hydrogels: synthesis, properties, applications
Authors: Urszula Maciołek | Małgorzata Kosińska‐Pezda | Tamara Martínez-Senra | Sonia Losada‐Barreiro | Carlos Bravo‐Díaz
Source: Molecules (review, 2025-11-06)
Field: Chemistry — Physical and Theoretical Chemistry

Flavonoid-Based Cocrystals: A Comprehensive Study on Their Synthesis, Characterization, Physicochemical Properties and Applications Flavonoids are naturally occurring compounds with reported anticancer, antimicrobial, anti-inflammatory, cardio-protective and antioxidant effects. They are increasingly incorporated in functional foods designed to promote health, enhance well-being, and support physical performance. However, their practical use is limited because of their low water solubility and poor absorption within the body. An effective strategy for developing new flavonoid-based formulations involves their transformation into molecular complexes (cocrystals) through cocrystallization, a method that has emerged a powerful tool to modulate the physicochemical and biological properties of polyphenols and other relevant drugs. Cocrystals are stabilized through non-covalent interactions, which can introduce new physicochemical properties to the original molecules (coformers) while retaining the chemical properties of the coformers, as no bonds are broken or formed. Flavonoid-based cocrystals can be obtained through a variety of methods using different coformers, and we aim here to review cocrystals containing flavonoids and coformers, with a focus on their methods of synthesis, physicochemical and biological characteristics, as well as their potential applications in both the food and pharmaceutical sectors. Polyphenol ; Solubility ; Molecule ; Food products ; Antioxidant ; Molecular conformation Crystallography and molecular interactions ; Luminescence and Fluorescent Materials ; Supramolecular Chemistry and Complexes
Authors: Rabindranath Lo | Bishwajit Ganguly
Source: Journal of Computational Chemistry (review, 2025-10-18)
Field: Chemistry — Organic Chemistry

A Dive Into Forty Years of Research on Organic Superbases: From Design to Applications This review highlights the design and applications of various types of neutral organic superbases, a relatively new and widely adopted class of Brønsted bases. These superbases offer complementary properties to conventional inorganic bases and have found increasing commercial application in modern synthetic methodologies. The recent advances in the computational design, synthesis, and catalytic behavior of organic superbases have been summarized. This article would embolden the development of novel, highly effective, and selective catalysts that enable efficient chemical transformations under metal-free conditions. Catalysis ; Organic synthesis ; Class (philosophy) ; World class Cyclopropane Reaction Mechanisms ; Asymmetric Hydrogenation and Catalysis ; Click Chemistry and Applications