jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Diego Hunt | Víctor Oestreicher | Martín Mizrahi | Félix G. Requejo | Matı́as Jobbágy
Source: Chemistry - A European Journal (article, 2020-07-28)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Unveiling the Occurrence of Co(III) in NiCo Layered Electroactive Hydroxides: The Role of Distorted Environments Co- and Ni-based layered hydroxides constitute a unique class of two-dimensional inorganic materials with exceptional chemical diversity, physicochemical properties and outstanding performance as supercapacitors and overall water splitting catalysts. Recently, the occurrence of Co(III) in these phases has been proposed as a key factor that enhance their electrochemical performance. However, the origin of this centers and control over its contents remains as an open question. We employed the Epoxide Route to synthesize a whole set of α-NiCo layered hydroxides. The PXRD and XAS characterization alert about the occurrence of Co(III) as a consequence of the increment in the Ni content. DFT+U simulation suggest that the shortening of the Co-O distance promotes a structural distortion in the Co environments, resulting in a double degeneration in the octahedral Co 3d orbitals. Hence, a strong modification of the electronic properties leaves the system prone to oxidation, by the appearance of Co localized electronic states on the Fermi level. This work combines a microscopic interpretation supported by a multiscale crystallochemical analysis, regarding the so-called synergistic redox behavior of Co and Ni, offering fundamental tools for the controllable design of highly efficient electroactive materials. To the best of our knowledge, this is the first computational-experimental investigation of the electronic and structural details of α-NiCo hydroxides, laying the foundation for the fine tuning of electronic properties in layered hydroxides. Layered double hydroxides ; Materials science ; Electrochemistry ; Electronic structure ; Redox ; Octahedron ; Atomic orbital ; Characterization (materials science) ; X-ray absorption spectroscopy ; Supercapacitor ; Nanotechnology ; Chemical physics ; Inorganic chemistry ; Crystallography ; Chemistry ; Computational chemistry ; Physical chemistry ; Hydroxide ; Crystal structure ; Metallurgy ; Absorption spectroscopy ; Physics ; Electrode ; Electron Supercapacitor Materials and Fabrication ; Electrocatalysts for Energy Conversion ; Copper-based nanomaterials and applications
Authors: Miguel Ferreira | Ilaria Francesca Rizzuti | Anna Lisa Palange | Maria Grazia Barbato | Valentina Di Francesco | Martina Di Francesco | Paolo Decuzzi
Source: Frontiers in Bioengineering and Biotechnology (article, 2020-02-19)
Field: Materials Science — Biomaterials

Optimizing the Pharmacological Properties of Discoidal Polymeric Nanoconstructs Against Triple-Negative Breast Cancer Cells Fine-tuning loading and release of therapeutic and imaging agents associated with polymeric matrices is a fundamental step in the preclinical development of novel nanomedicines. Here, 1,000 × 400 nm Discoidal Polymeric Nanoconstructs (DPNs) were realized via a top-down, template-based fabrication approach, mixing together poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol)-diacrylate (PEG-DA) chains in a single polymer paste. Two different loading strategies were tested, namely the "direct loading" and the "absorption loading." In the first case, the agent was directly mixed with the polymeric paste to realize DPNs whereas, in the second case, DPNs were first lyophilized and then rehydrated upon exposure to a concentrated aqueous solution of the agent. Under these two loading conditions, the encapsulation efficiencies and release profiles of different agents were systematically assessed. Specifically, six agents were realized by conjugating lipid chains (DSPE) or polymeric chains (PEG) to the near-infrared imaging molecule Cy5 (DSPE-Cy5 A and DSPE-Cy5 B); the chemotherapeutic molecules methotrexate (DSPE-MTX and PEG-MTX) and doxorubicin (LA-DOX and DSPE-DOX). Moderately hydrophobic compounds with low molecular weights (MW) returned encapsulation efficiencies as high as 80% for the absorption loading. In general, direct loading was associated with encapsulation efficiencies lower than 1%. The agent hydrophobicity and MW were shown to be critical also in tailoring the release profiles from DPNs. On triple-negative breast cancer cells (MDA-MB-231), absorption loaded DOX-DPNs showed cytotoxic activities comparable to free DOX but slightly delayed in time. Preliminary <i>in vivo</i> studies demonstrated the high stability of Cy5-DPNs. Collectively, these results demonstrate that the pharmacological properties of DPNs can be finely optimized by changing the loading strategies (direct vs. absorption) and compound attributes (hydrophobicity and molecular weight). Materials science ; Aqueous solution ; PEG ratio ; Polymer ; Ethylene glycol ; Doxorubicin ; Chemical engineering ; Nanotechnology ; Chemistry ; Organic chemistry ; Chemotherapy Nanoparticle-Based Drug Delivery ; Nanoplatforms for cancer theranostics ; Graphene and Nanomaterials Applications
Authors: Fan Yang | Wenhui Hu | Chongqing Yang | Margaret Patrick | Andrew L. Cooksy | Jian Zhang | Jeffery A. Aguiar | Chengcheng Fang | Ying‐Hua Zhou | Ying Shirley Meng | Jier Huang | Jing Gu
Source: Angewandte Chemie (article, 2020-01-08)
Field: Chemistry — Inorganic Chemistry

Tuning Internal Strain in Metal–Organic Frameworks via Vapor Phase Infiltration for CO<sub>2</sub> Reduction Abstract A gas‐phase approach to form Zn coordination sites on metal–organic frameworks (MOFs) by vapor‐phase infiltration (VPI) was developed. Compared to Zn sites synthesized by the solution‐phase method, VPI samples revealed approximately 2.8 % internal strain. Faradaic efficiency towards conversion of CO 2 to CO was enhanced by up to a factor of four, and the initial potential was positively shifted by 200–300 mV. Using element‐specific X‐ray absorption spectroscopy, the local coordination environment of the Zn center was determined to have square‐pyramidal geometry with four Zn−N bonds in the equatorial plane and one Zn‐OH 2 bond in the axial plane. The fine‐tuned internal strain was further supported by monitoring changes in XRD and UV/Visible absorption spectra across a range of infiltration cycles. The ability to use internal strain to increase catalytic activity of MOFs suggests that applying this strategy will enhance intrinsic catalytic capabilities of a variety of porous materials. Porosity ; Absorption spectroscopy ; Catalysis ; Metal-organic framework ; Metal ; Materials science ; Phase (matter) ; Infrared spectroscopy ; Extended X-ray absorption fine structure ; Chemistry ; Analytical Chemistry (journal) ; Chemical engineering ; Composite material ; Physical chemistry ; Organic chemistry ; Metallurgy ; Optics ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Carbon dioxide utilization in catalysis
Authors: Jorge Romero | M. Varela | Mhamed Assebban | Víctor Oestreicher | Alejandra Guedeja‐Marrón | J.L. Jordá | Gonzalo Abellán | Eugenio Coronado
Source: Chemical Science (article, 2020-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Insights into the formation of metal carbon nanocomposites for energy storage using hybrid NiFe layered double hydroxides as precursors NiFe-carbon magnetic nanocomposites prepared using hybrid sebacate intercalated layered double hydroxides (LDHs) as precursors are shown to be of interest as supercapacitors. Here, the low-temperature formation mechanism of these materials has been deciphered by means of a combined study using complementary <i>in situ</i> (temperature-dependent) techniques. Specifically, studies involving X-ray powder diffraction, thermogravimetry coupled to mass spectrometry (TG-MS), statistical Raman spectroscopy (SRS), aberration-corrected scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS) have been carried out. The experimental results confirm the early formation of FeNi<sub>3</sub> nanoparticles at <i>ca.</i> 200-250 °C, preceding the concerted collapse of the starting NiFe-LDH laminar structure over just 50 °C (from 350 to 400 °C). At the same time, the catalytic interactions between the metallic atoms and the organic molecules permit the concomitant formation of a graphitic carbon matrix leading to the formation of the final FeNi<sub>3</sub>-carbon nanocomposite. Furthermore, <i>in situ</i> temperature-dependent experiments in the presence of the intrinsic magnetic field of the STEM-EELS allow observing the complete metal segregation of Ni and Fe even at 400 °C. These results provide fundamental insights into the catalytic formation of carbon-based nanocomposites using LDHs as precursors and pave the way for the fine-tuning of their properties, with special interest in the field of energy storage and conversion. Layered double hydroxides ; Nanocomposite ; Carbon fibers ; Materials science ; Hybrid material ; Chemical engineering ; Metal ; Characterization (materials science) ; Composite number ; Inorganic chemistry ; Nanotechnology ; Chemistry ; Metallurgy ; Composite material ; Hydroxide Supercapacitor Materials and Fabrication ; Layered Double Hydroxides Synthesis and Applications ; Advancements in Battery Materials
Authors: Ishfaq Ahmad | Javeed Mahmood | Jong‐Beom Baek
Source: Small Science (article, 2020-10-21)
Field: Materials Science — Materials Chemistry

Recent Progress in Porous Fused Aromatic Networks and Their Applications Porous materials are ubiquitous in nature and play central roles in ecosystems and human life. Porous fused aromatic networks (P-FANs) are emerging as a new class of porous organic materials, which can be precisely constructed from organic precursors via the formation of irreversible fused aromatic rings. Despite the luculent advantages offered by P-FANs, the research community has conventionally focused on more synthetically accessible covalent organic frameworks (COFs), which mostly involve reversible condensation reactions. An overview of the trend in the field of P-FANs and their possible applications in different fields, including proton conduction, catalysis, gas storage, supercapacitors, and optoelectronics, is presented herein. Nanotechnology ; Porous medium ; Porosity ; Materials science ; Supercapacitor ; Organic chemistry ; Chemistry ; Electrochemistry ; Electrode Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Luminescence and Fluorescent Materials
Authors: K. Velmurugan | Makesh Mohan | Zhong‐Yuan Lu | Kaiya Wang | Minzan Zuo | Xiao‐Yu Hu
Source: Materials Advances (article, 2020-01-01)
Field: Materials Science — Biomaterials

Macrocycles-assisted polymeric self-assemblies fabricated by host–guest complexation and their applications Macrocycles-assisted polymeric self-assemblies and their potential applications are systematically summarized for the production of smart materials. Nanotechnology ; Materials science ; Host (biology) Supramolecular Self-Assembly in Materials ; Supramolecular Chemistry and Complexes ; Covalent Organic Framework Applications
Authors: A. Pia P. Kröger | Jan-Willem D. Paats | Roy J. E. A. Boonen | Naomi M. Hamelmann | Jos M. J. Paulusse
Source: Polymer Chemistry (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Pentafluorophenyl-based single-chain polymer nanoparticles as a versatile platform towards protein mimicry Pentafluorophenyl-single chain polymer nanoparticles are readily conjugated with functional amines enabling facile SCNP modification, adjustment of physicochemical properties, and even protein mimicry. Mimicry ; Conjugated system ; Nanoparticle ; Polymer ; Chemistry ; Molecular mimicry ; Chain (unit) ; Combinatorial chemistry ; Single chain ; Nanotechnology ; Materials science ; Organic chemistry ; Antibody ; Biology Advanced Polymer Synthesis and Characterization ; Chemical Synthesis and Analysis ; Dendrimers and Hyperbranched Polymers
Authors: Marcello La Rosa | Emily H. Payne | Alberto Credi
Source: ChemistryOpen (review, 2020-02-01)
Field: Materials Science — Materials Chemistry

Semiconductor Quantum Dots as Components of Photoactive Supramolecular Architectures Abstract Luminescent quantum dots (QDs) are colloidal semiconductor nanocrystals consisting of an inorganic core covered by a molecular layer of organic surfactants. Although QDs have been known for more than thirty years, they are still attracting the interest of researchers because of their unique size‐tunable optical and electrical properties arising from quantum confinement. Moreover, the controlled decoration of the QD surface with suitable molecular species enables the rational design of inorganic‐organic multicomponent architectures that can show a vast array of functionalities. This minireview highlights the recent progress in the use of surface‐modified QDs – in particular, those based on cadmium chalcogenides – as supramolecular platforms for light‐related applications such as optical sensing, triplet photosensitization, photocatalysis and phototherapy. Quantum dot ; Nanotechnology ; Supramolecular chemistry ; Nanocrystal ; Semiconductor ; Materials science ; Photocatalysis ; Optoelectronics ; Chemistry ; Molecule Quantum Dots Synthesis And Properties ; Nanocluster Synthesis and Applications ; Chalcogenide Semiconductor Thin Films
Authors: Giulia Neri | Giuliana Mion | Andrea Pizzi | Wanda Celentano | Linda Chaabane | Michele R. Chierotti | Roberto Gobetto | Min Li | Piergiorgio Messa | Floryan De Campo | Francesco Cellesi | Pierangelo Metrangolo | Francesca Baldelli Bombelli
Source: Chemistry - A European Journal (article, 2020-06-09)
Field: Chemistry — Inorganic Chemistry

Fluorinated PLGA Nanoparticles for Enhanced Drug Encapsulation and <sup>19</sup>F NMR Detection In the continuous search for multimodal systems with combined diagnostic and therapeutic functions, several efforts have been made to develop multifunctional drug delivery systems. In this work, through a covalent approach, a new class of fluorinated poly(lactic-co-glycolic acid) co-polymers (F-PLGA) were designed that contain an increasing number of magnetically equivalent fluorine atoms. In particular, two novel compounds, F<sub>3</sub> -PLGA and F<sub>9</sub> -PLGA, were synthesized and their chemical structure and thermal stability were analyzed by solution NMR, DSC, and TGA. The obtained F-PLGA compounds were proven to form in aqueous solution colloidal stable nanoparticles (NPs) displaying a strong <sup>19</sup> F NMR signal. The fluorinated NPs also showed an enhanced ability to load hydrophobic drugs containing fluorine atoms compared to analogous pristine PLGA NPs. Preliminary in vitro studies showed high cell viability and the NP ability to intracellularly deliver and release a functioning drug. PLGA ; Nanoparticle ; Polymer ; Aqueous solution ; Covalent bond ; Drug delivery ; Thermal stability ; Glycolic acid ; Materials science ; Chemical engineering ; Fluorine ; Colloid ; Chemistry ; Nanotechnology ; Nuclear chemistry ; Combinatorial chemistry ; Organic chemistry ; Lactic acid Inorganic Fluorides and Related Compounds ; Connective tissue disorders research ; Fluorine in Organic Chemistry
Authors: Ichiro Hisaki | Qin Ji | Kiyonori Takahashi | Norimitsu Tohnai | Takayoshi Nakamura
Source: Crystal Growth & Design (article, 2020-03-24)
Field: Chemistry — Inorganic Chemistry

Positional Effects of Annelated Pyrazine Rings on Structure and Stability of Hydrogen-Bonded Frameworks of Hexaazatrinaphthylene Derivatives A porous hydrogen-bonded organic framework (HOF) composed of N-hetero π-conjugated molecules (Nπ-HOF) is a promising candidate for multifunctional porous materials. However, such HOFs are still limited and only a handful of examples have been reported. In this study, we investigated the positional effects of annelated pyrazine rings on the structure and stability of Nπ-HOFs to establish a design principle for Nπ-HOFs. A new isomer of hexaazatrinaphthylene (CPBTQ) was synthesized and subjected to Nπ-HOF construction, activation, and an evaluation of stability and permanent porosity. A comparison between two kinds of Nπ-HOFs composed of isomers (CPBTQ and CPHATN) possessing three pyrazine rings annelated at different positions indicates that the positional difference of the pyrazine rings strongly affects the conformation of the peripheral phenylene groups, which then leads to different structures and stabilities of the Nπ-HOFs. The activated Nπ-HOF composed of CPBTQ (CPBTQ-1a) is revealed to exhibit a Brunauer–Emmett–Teller surface area of 471 m2 g–1 and shows HCl responsiveness thanks to the basic pyrazine rings annelated to the triphenylene core. We believe that the present results can contribute not only to the construction of multifunctional porous materials but also to the chemistry of heteroaromatic compounds. Pyrazine ; Chemistry ; Molecule ; Phenylene ; Materials science ; Stereochemistry ; Organic chemistry ; Polymer Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Supramolecular Chemistry and Complexes
Authors: Maria Heilmann | Hannes Kulla | Carsten Prinz | Ralf Bienert | Uwe Reinholz | Ana Guilherme Buzanich | Franziska Emmerling
Source: Nanomaterials (article, 2020-04-09)
Field: Chemistry — Organic Chemistry

Advances in Nickel Nanoparticle Synthesis via Oleylamine Route Nickel nanoparticles are an active research area due to their multiple applications as catalysts in different processes. A variety of preparation techniques have been reported for the synthesis of these nanoparticles, including solvothermal, microwave-assisted, and emulsion techniques. The well-studied solvothermal oleylamine synthesis route comes with the drawback of needing standard air-free techniques and often space-consuming glassware. Here, we present a facile and straightforward synthesis method for size-controlled highly monodisperse nickel nanoparticles avoiding the use of, e.g., Schlenk techniques and space-consuming labware. The nanoparticles produced by this novel synthetic route were investigated using small-angle X-ray scattering, transmission electron microscopy, X-ray diffraction, and X-ray spectroscopy. The nanoparticles were in a size range of 4‒16 nm, show high sphericity, no oxidation, and no agglomeration after synthesis. Oleylamine ; Nickel ; Nanoparticle ; Materials science ; Nanotechnology ; Chemical engineering ; Metallurgy ; Engineering Nanomaterials for catalytic reactions ; Catalytic Processes in Materials Science ; Copper-based nanomaterials and applications
Authors: Nicholas McKitterick | Tugrul Cem Bicak | Peter A. G. Cormack | Léon Reubsaet | Trine Grønhaug Halvorsen
Source: Analytica Chimica Acta (article, 2020-10-15)
Field: Chemistry — Analytical Chemistry

Facilitating serum determination of neuron specific enolase at clinically relevant levels by coupling on-line molecularly imprinted solid-phase extraction to LC-MS/MS The identification and quantification of biomarkers is essential for the diagnosis, treatment, and long-term monitoring of many human diseases. In the present work, macromolecular synthetic receptors with pre-determined affinity and selectivity for the signature peptide of a prognostically significant small cell lung cancer (SCLC) biomarker - neuron-specific enolase (NSE) - were prepared in a porous polymer microsphere format using a template-directed synthesis strategy performed under precipitation polymerization conditions. The polymer microspheres were packed into short trap columns and then exploited as molecularly selective sorbents in a fully automated, on-line molecularly imprinted solid-phase extraction (MISPE) protocol. The on-line MISPE protocol was optimised with respect to the composition of the loading mobile phase, the flow rate, and the extraction time. The molecularly imprinted polymers (MIPs) showed high affinity and useful selectivity for the peptide target - the hexapeptide ELPLYR - compared to non-imprinted control polymers. The MIPs were able to retain the biomarker on-column for extraction times of up to 20 min, and the on-line MISPE method enabled complete recovery of the biomarker over the linear range 10-100 ng mL<sup>-1</sup> when the biomarker was present in spiked ammonium bicarbonate solution (R<sup>2</sup> = 0.994). For extractions of ELPLYR from very complex biological matrices, the recoveries of ELPLYR from reversed-phase SPE (RP-SPE)-treated and untreated digested human serum were 100.8 ± 6.2% and 61.6 ± 1.9%, respectively. Extractions of ELPLYR from spiked untreated digested serum were linear in the range of 7.5-375 ng mL<sup>-1</sup> (R<sup>2</sup> = 0.99). The limit of detection (LOD) and limit of quantification (LOQ) for the biomarker in digested serum were estimated to be 1.8 ng mL<sup>-1</sup> and 6.0 ng mL<sup>-1</sup>, respectively, which is below the median reference level of NSE in humans (8.6 ng mL<sup>-1</sup>). This work sets in place the basis for a new diagnostic tool for SCLC that is sensitive, robust, automated, and antibody-free, and which works very well with complex human plasma samples. Molecularly imprinted polymer ; Chemistry ; Solid phase extraction ; Chromatography ; Precipitation polymerization ; Extraction (chemistry) ; Enolase ; Ammonium bicarbonate ; Detection limit ; Biomarker ; Molecular imprinting ; Polymerization ; Selectivity ; Polymer ; Radical polymerization ; Biochemistry Analytical chemistry methods development ; Mass Spectrometry Techniques and Applications ; Advanced biosensing and bioanalysis techniques
Authors: Zhuo Li | Bing Wang | Bingbing Zhang | Guo-Yi Cui | Fenyan Zhang | Long Xu | Lin‐Yu Jiao | Lingyan Pang | Xiaoxun Ma
Source: ChemistryOpen (article, 2020-10-01)
Field: Materials Science — Materials Chemistry

Synthesis, Characterization and Optoelectronic Property of Axial‐Substituted Subphthalocyanines Two novel substituted subphthalocyanines have been prepared introducing m-hydroxybenzoic acid and m-hydroxyphenylacetic acid into the axial position of bromo-subphthalocyanine. The compounds have been characterized by Fourier transform infrared (FT-IR), Nuclear Magnetic Resonance (NMR) and single-crystal X-rays diffraction (XRD) methods. Their photophysical properties show that the axial substitution results into a relatively higher fluorescence quantum efficiency (<i>Φ</i><sub>F</sub>=5.74 for m-hydroxybenzoic acid and 9.09 % for m-hydroxyphenylacetic acid) in comparison with that of the prototype compound, despite the almost negligible influence on the maximum absorption or the emission position. Moreover, the electrochemical behaviors show that the axial-substituted subphthalocyanines also exhibit enhanced specific capacitances of 395 F/g (m-hydroxybenzoic acid) and 362 F/g (m-hydroxyphenylacetic acid) compared with 342 F/g (the prototype) to the largest capacitance at the scan rate of 5 mV/s, and the significantly larger capacitance retentions of 83.6 % and 82.1 % <i>versus</i> 37.3 % upon density up to 3 A/g. These results show the potential of these axial-substituted subphthalocyanines in the use as organic photovoltaics and supercapacitors. Chemistry ; Capacitance ; Absorption (acoustics) ; Electrochemistry ; Proton NMR ; Fluorescence ; Fourier transform infrared spectroscopy ; Materials science ; Analytical Chemistry (journal) ; Physical chemistry ; Organic chemistry ; Chemical engineering ; Optics ; Electrode Porphyrin and Phthalocyanine Chemistry ; Photosynthetic Processes and Mechanisms ; Organic Electronics and Photovoltaics