jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: M. N. Timofeeva | Valentina N. Panchenko | Sung Hwa Jhung
Source: International Journal of Molecular Sciences (review, 2023-02-22)
Field: Chemistry — Inorganic Chemistry

Insights into the Structure–Property–Activity Relationship of Zeolitic Imidazolate Frameworks for Acid–Base Catalysis Zeolitic imidazolate frameworks (ZIFs) have been extensively examined for their potential in acid-base catalysis. Many studies have demonstrated that ZIFs possess unique structural and physicochemical properties that allow them to demonstrate high activity and yield products with high selectivity. Herein, we highlight the nature of ZIFs in terms of their chemical formulation and the textural, acid-base, and morphological properties that strongly affect their catalytic performance. Our primary focus is the application of spectroscopic methods as instruments for analyzing the nature of active sites because these methods can allow an understanding of unusual catalytic behavior from the perspective of the structure-property-activity relationship. We examine several reactions, such as condensation reactions (the Knoevenagel condensation and Friedländer reactions), the cycloaddition of CO<sub>2</sub> to epoxides, the synthesis of propylene glycol methyl ether from propylene oxide and methanol, and the cascade redox condensation of 2-nitroanilines with benzylamines. These examples illustrate the broad range of potentially promising applications of Zn-ZIFs as heterogeneous catalysts. Knoevenagel condensation ; Chemistry ; Zeolitic imidazolate framework ; Catalysis ; Propylene oxide ; Selectivity ; Combinatorial chemistry ; Condensation reaction ; Organic chemistry ; Metal-organic framework ; Adsorption ; Polymer Metal-Organic Frameworks: Synthesis and Applications ; Carbon dioxide utilization in catalysis ; Covalent Organic Framework Applications
Authors: Yang Tang | Guanfeng Ji | Hanning Li | Hui Gao | Cheng He | Liang Zhao | Chunying Duan
Source: Inorganic Chemistry Frontiers (article, 2023-01-01)
Field: Chemistry — Inorganic Chemistry

Ligand-regulated photoinduced electron transfer within metal–organic frameworks for efficient photocatalysis By judiciously controlling the twisted conjugation between ligands and coordinated carboxylates to inhibit intramolecular photoinduced electron transfer process, an acridone-based metal–organic framework was obtained for efficient photocatalysis. Photocatalysis ; Intramolecular force ; Photoinduced electron transfer ; Electron transfer ; Acridone ; Photochemistry ; Metal ; Ligand (biochemistry) ; Chemistry ; Metal-organic framework ; Materials science ; Catalysis ; Stereochemistry ; Organic chemistry ; Receptor ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Advanced Photocatalysis Techniques ; Polyoxometalates: Synthesis and Applications
Authors: Panangattukara Prabhakaran Praveen Kumar | Ritu Mahajan
Source: Nanotheranostics (review, 2023-11-15)
Field: Materials Science — Biomaterials

Gold Polymer Nanomaterials: A Promising Approach for Enhanced Biomolecular Imaging Gold nanoparticles (AuNPs) possess unique optical properties, making them highly attractive nanomaterials for biomedical research. By exploiting the diverse optical characteristics of various gold nanostructures, significant enhancements can be achieved in biosensing and biomedical imaging fields. The potential of AuNPs can be enhanced by creating hybrid nanocomposites with polymers, which offer supplementary functionalities, responsiveness, and enhanced biocompatibility. Moreover, polymers can modify the surface charges of AuNPs, thereby improving or controlling the efficiency of cellular uptake and the distribution of these nanoparticles within the body. Polymer modification using AuNPs offers a wide array of benefits, including improved sensitivity, specificity, speed, contrast, resolution, and penetration depth. By incorporating AuNPs into the polymer matrix, these enhancements synergistically enhance the overall performance of various applications. This versatile approach opens promising possibilities in fields such as biomedicine, nanotechnology, and sensor development, providing a powerful platform for advanced research and technological innovations. In this review, the recent advancements in polymer-AuNPs synthesis and their applications in bioimaging will be covered. Prospects and challenges associated with polymer-AuNPs-based bioimaging agents in preclinical and clinical investigations will be discussed. Nanotechnology ; Colloidal gold ; Materials science ; Nanomaterials ; Polymer ; Biocompatibility ; Biosensor ; Smart polymer ; Nanoparticle Nanoparticle-Based Drug Delivery ; Dendrimers and Hyperbranched Polymers
Authors: Valentyn Pozhydaiev | Cyprien Muller | Joseph Moran | David Lebœuf
Source: Angewandte Chemie International Edition (review, 2023-08-21)
Field: Chemistry — Organic Chemistry

Catalytic Synthesis of β‐(Hetero)arylethylamines: Modern Strategies and Advances β-(Hetero)arylethylamines appear in a myriad of pharmaceuticals due to their broad spectrum of biological properties, making them prime candidates for drug discovery. Conventional methods for their preparation often require engineered substrates that limit the flexibility of the synthetic routes and the diversity of compounds that can be accessed. Consequently, methods that provide rapid and versatile access to those scaffolds remain limited. To overcome these challenges, synthetic chemists have designed innovative and modular strategies to access the β-(hetero)arylethylamine motif, paving the way for their more extensive use in future pharmaceuticals. This review outlines recent progresses in the synthesis of (hetero)arylethylamines and emphasizes how these innovations have enabled new levels of molecular complexity, selectivity, and practicality. Nanotechnology ; Flexibility (engineering) ; Modular design ; Computer science ; Broad spectrum ; Drug discovery ; Combinatorial chemistry ; Biochemical engineering ; Chemistry ; Materials science ; Engineering Catalytic C–H Functionalization Methods ; Synthesis and Catalytic Reactions ; Sulfur-Based Synthesis Techniques
Authors: Antonello Raponi | Salvatore Romano | Giuseppe Battaglia | Antonio Buffo | Marco Vanni | Andrea Cipollina | Daniele Marchisio
Source: Crystal Growth & Design (article, 2023-06-23)
Field: Materials Science — Materials Chemistry

Computational Modeling of Magnesium Hydroxide Precipitation and Kinetics Parameters Identification Magnesium is a critical raw material and its recovery as Mg(OH)<sub>2</sub> from saltwork brines can be realized via precipitation. The effective design, optimization, and scale-up of such a process require the development of a computational model accounting for the effect of fluid dynamics, homogeneous and heterogeneous nucleation, molecular growth, and aggregation. The unknown kinetics parameters are inferred and validated in this work by using experimental data produced with a T<sub>2mm</sub>-mixer and a T<sub>3mm</sub>-mixer, guaranteeing fast and efficient mixing. The flow field in the T-mixers is fully characterized by using the <i>k</i>-<i>ε</i> turbulence model implemented in the computational fluid dynamics (CFD) code OpenFOAM. The model is based on a simplified plug flow reactor model, instructed by detailed CFD simulations. It incorporates Bromley's activity coefficient correction and a micro-mixing model for the calculation of the supersaturation ratio. The population balance equation is solved by exploiting the quadrature method of moments, and mass balances are used for updating the reactive ions concentrations, accounting for the precipitated solid. To avoid unphysical results, global constrained optimization is used for kinetics parameters identification, exploiting experimentally measured particle size distribution (PSD). The inferred kinetics set is validated by comparing PSDs at different operative conditions both in the T<sub>2mm</sub>-mixer and the T<sub>3mm</sub>-mixer. The developed computational model, including the kinetics parameters estimated for the first time in this work, will be used for the design of a prototype for the industrial precipitation of Mg(OH)<sub>2</sub> from saltwork brines in an industrial environment. Computational fluid dynamics ; Chemistry ; Turbulence ; Mixing (physics) ; Population balance equation ; Biological system ; Thermodynamics ; Mechanics ; Population ; Physics Magnesium Oxide Properties and Applications ; Calcium Carbonate Crystallization and Inhibition ; Phosphorus and nutrient management
Authors: Brandon Johnston | Alan J. Grodzinsky | Paula T. Hammond
Source: Soft Matter (article, 2023-01-01)
Field: Materials Science — Polymers and Plastics

Charge shielding effects of PEG bound to NH<sub>2</sub>-terminated PAMAM dendrimers – an experimental approach Cationic poly(amido amine) (PAMAM) dendrimers exhibit great potential for use in drug delivery, but their high charge density leads to an inherent cytotoxicity. To increase biocompatibility, many studies have attached poly(ethylene glycol) (PEG) chains to the dendrimer surface. It is unclear how these tethered PEG chains influence the physicochemical properties of the dendrimer. Here, we develop a fluorescence-based assay utilizing anionic biological tissue to quantify the electrostatic binding affinity of a library of PEG-PAMAM conjugates with various PEG chain lengths and grafting densities. We find that covalently bound PEG chains reduce the electrostatic binding affinity more significantly than what can be achieved through covalent bonds only. Contrary to previous thought, this reduction is not explained by the steric hindrance effects of PEG chains, suggesting that other, non-covalent interactions between PEG and PAMAM are present. Using acetylated PAMAM conjugates, we convert electrostatic binding affinity to the number of charged amines accessible to the physiological environment. These data, coupled with <sup>1</sup>H-NMR, allows us to study more closely the non-covalent interactions between PEG and PAMAM. We find that increasing PEG chain length increases the number of non-covalent interactions. Additionally, at low grafting densities, increasing the number of PEG chains on the PAMAM surface also increases the non-covalent interactions. At higher grafting densities, however, PEG chains sterically repel one another, forcing chains to elongate away from the surface and reducing the number of interactions between PAMAM and individual PEG chains. The data presented here provides a framework for a more precise mechanistic understanding of how the length and density of tethered PEG chains on PAMAM dendrimers influence drug delivery properties. Covalent bond ; Dendrimer ; PEG ratio ; Steric effects ; Chemistry ; Ethylene glycol ; Grafting ; Cationic polymerization ; Polymer chemistry ; Combinatorial chemistry ; Organic chemistry ; Polymer Dendrimers and Hyperbranched Polymers ; RNA Interference and Gene Delivery ; Polymer Surface Interaction Studies
Authors: David Coronel-Meneses | Calef Sánchez‐Trasviña | Imma Ratera | Karla Mayolo‐Deloisa
Source: Frontiers in Bioengineering and Biotechnology (review, 2023-05-09)
Field: Materials Science — Biomaterials

Strategies for surface coatings of implantable cardiac medical devices Cardiac medical devices (CMDs) are required when the patient's cardiac capacity or activity is compromised. To guarantee its correct functionality, the building materials in the development of CMDs must focus on several fundamental properties such as strength, stiffness, rigidity, corrosion resistance, etc. The challenge is more significant because CMDs are generally built with at least one metallic and one polymeric part. However, not only the properties of the materials need to be taken into consideration. The biocompatibility of the materials represents one of the major causes of the success of CMDs in the short and long term. Otherwise, the material will lead to several problems of hemocompatibility (e.g., protein adsorption, platelet aggregation, thrombus formation, bacterial infection, and finally, the rejection of the CMDs). To enhance the hemocompatibility of selected materials, surface modification represents a suitable solution. The surface modification involves the attachment of chemical compounds or bioactive compounds to the surface of the material. These coatings interact with the blood and avoid hemocompatibility and infection issues. This work reviews two main topics: 1) the materials employed in developing CMDs and their key characteristics, and 2) the surface modifications reported in the literature, clinical trials, and those that have reached the market. With the aim of providing to the research community, considerations regarding the choice of materials for CMDs, together with the advantages and disadvantages of the surface modifications and the limitations of the studies performed. Materials science ; Biocompatibility ; Surface modification ; Nanotechnology ; Computer science ; Mechanical engineering Electrospun Nanofibers in Biomedical Applications ; Polymer Surface Interaction Studies ; Metal and Thin Film Mechanics
Authors: María A. Fanovich | Ernesto Di Maio | Aurelio Salerno
Source: Journal of Functional Biomaterials (review, 2023-09-19)
Field: Materials Science — Polymers and Plastics

Current Trend and New Opportunities for Multifunctional Bio-Scaffold Fabrication via High-Pressure Foaming Biocompatible and biodegradable foams prepared using the high-pressure foaming technique have been widely investigated in recent decades as porous scaffolds for in vitro and in vivo tissue growth. In fact, the foaming process can operate at low temperatures to load bioactive molecules and cells within the pores of the scaffold, while the density and pore architecture, and, hence, properties of the scaffold, can be finely modulated by the proper selection of materials and processing conditions. Most importantly, the high-pressure foaming of polymers is an ideal choice to limit and/or avoid the use of cytotoxic and tissue-toxic compounds during scaffold preparation. The aim of this review is to provide the reader with the state of the art and current trend in the high-pressure foaming of biomedical polymers and composites towards the design and fabrication of multifunctional scaffolds for tissue engineering. This manuscript describes the application of the gas foaming process for bio-scaffold design and fabrication and highlights some of the most interesting results on: (1) the engineering of porous scaffolds featuring biomimetic porosity to guide cell behavior and to mimic the hierarchical architecture of complex tissues, such as bone; (2) the bioactivation of the scaffolds through the incorporation of inorganic fillers and drugs. Scaffold ; Materials science ; Fabrication ; Porosity ; Tissue engineering ; Polymer ; Nanotechnology ; Process (computing) ; Biomedical engineering ; Composite material ; Computer science Polymer Foaming and Composites ; biodegradable polymer synthesis and properties ; Polymer composites and self-healing
Authors: Myunggi Jung | Joanna E. Muir | Vincent N. G. Lindsay
Source: Tetrahedron (article, 2023-02-02)
Field: Chemistry — Organic Chemistry

Expedient synthesis of spiro[3.3]heptan-1-ones via strain-relocating semipinacol rearrangements Chemistry ; Strain (injury) ; Combinatorial chemistry ; Stereochemistry Oxidative Organic Chemistry Reactions ; Synthetic Organic Chemistry Methods ; Chemical synthesis and alkaloids
Authors: Chiranjib Ghosh | Arka Dey | Iman Biswas | Rajeev Kumar Gupta | Vikram Singh Yadav | Ashish Yadav | Neha Yadav | Hongyu Zheng | M. Henini | Aniruddha Mondal
Source: Nano Materials Science (article, 2023-11-24)
Field: Materials Science — Materials Chemistry

CuO–TiO2 based self-powered broad band photodetector An efficient room-temperature self-powered, broadband (300 ​nm–1100 nm) photodetector based on a CuO–TiO2/TiO2/p-Si(100) heterostructure is demonstrated. The CuO–TiO2 nanocomposites were grown in a two-zone horizontal tube furnace on a 40 ​nm TiO2 thin film deposited on a p-type Si(100) substrate. The CuO–TiO2/TiO2/p-Si(100) devices exhibited excellent rectification characteristics under dark and individual photo-illumination conditions. The devices showed remarkable photo-response under broadband (300–1100 ​nm) light illumination at zero bias voltage, indicating the achievement of highly sensitive self-powered photodetectors at visible and near-infrared light illuminations. The maximum response of the devices is observed at 300 ​nm for an illumination power of 10 ​W. The response and recovery times were calculated as 86 ​ms and 78 ​ms, respectively. Moreover, under a small bias, the devices showed a prompt binary response by altering the current from positive to negative under illumination conditions. The main reason behind this binary response is the low turn-on voltage and photovoltaic characteristics of the devices. Under illumination conditions, the generation of photocurrent is due to the separation of photogenerated electron-hole pairs within the built-in electric field at the CuO–TiO2/TiO2 interface. These characteristics make the CuO–TiO2/TiO2 broadband photodetectors suitable for applications that require high response speeds and self-sufficient functionality. Photodetector ; Materials science ; Optoelectronics ; Photocurrent ; Heterojunction ; Rectification ; Dark current ; Broadband ; Biasing ; Optical power ; Thin film ; Voltage ; Optics ; Nanotechnology ; Laser ; Electrical engineering ; Physics ZnO doping and properties ; Copper-based nanomaterials and applications ; Quantum Dots Synthesis And Properties
Authors: Ji Yong Choi | Minyan Wang | Brianna Check | Michael Stodolka | Kyle Tayman | Sandeep Sharma | Jihye Park
Source: Small (article, 2023-01-15)
Field: Chemistry — Inorganic Chemistry

Linker‐Based Bandgap Tuning in Conductive MOF Solid Solutions Herein, the synthesis of Cu<sub>3</sub> (HAB)<sub>x</sub> (TATHB)<sub>2-x</sub> (HAB: hexaaminobenzene, TATHB: triaminotrihydroxybenzene) is reported. Synthetic improvement of Cu<sub>3</sub> (TATHB)<sub>2</sub> leads to a more crystalline framework with higher electrical conductivity value than previously reported. The improved crystallinity and analogous structure between TATHB and HAB enable the synthesis of Cu<sub>3</sub> (HAB)<sub>x</sub> (TATHB)<sub>2-x</sub> with ligand compositions precisely controlled by precursor ratios. The electrical conductivity is tuned from 4.2 × 10<sup>-8</sup> to 2.9 × 10<sup>-5</sup> S cm<sup>-1</sup> by simply increasing the nitrogen content in the crystal lattice. Furthermore, computational calculation supports that the solid solution facilitates the band structure tuning. It is envisioned that the findings not only shed light on the ligand-dependent structure-property relationship but create new prospects in synthesizing multicomponent electrically conductive metal-organic frameworks (MOFs) for tailoring optoelectronic device applications. Crystallinity ; Materials science ; Electrical conductor ; Linker ; Band gap ; Metal-organic framework ; Electrical resistivity and conductivity ; Crystal structure ; Conductivity ; Ligand (biochemistry) ; Solid solution ; Nanotechnology ; Electrically conductive ; Optoelectronics ; Chemical engineering ; Crystallography ; Chemistry ; Computer science ; Physical chemistry ; Composite material ; Electrical engineering Metal-Organic Frameworks: Synthesis and Applications ; MXene and MAX Phase Materials ; Advanced Photocatalysis Techniques
Authors: Paula Alfonso-Triguero | Júlia Lorenzo | Ana Paula Candiota | Carles Arús | Daniel Ruiz‐Molina | Fernando Novio
Source: Nanomaterials (review, 2023-05-12)
Field: Materials Science — Biomaterials

Platinum-Based Nanoformulations for Glioblastoma Treatment: The Resurgence of Platinum Drugs? Current therapies for treating Glioblastoma (GB), and brain tumours in general, are inefficient and represent numerous challenges. In addition to surgical resection, chemotherapy and radiotherapy are presently used as standards of care. However, treated patients still face a dismal prognosis with a median survival below 15-18 months. Temozolomide (TMZ) is the main chemotherapeutic agent administered; however, intrinsic or acquired resistance to TMZ contributes to the limited efficacy of this drug. To circumvent the current drawbacks in GB treatment, a large number of classical and non-classical platinum complexes have been prepared and tested for anticancer activity, especially platinum (IV)-based prodrugs. Platinum complexes, used as alkylating agents in the anticancer chemotherapy of some malignancies, are though often associated with severe systemic toxicity (i.e., neurotoxicity), especially after long-term treatments. The objective of the current developments is to produce novel nanoformulations with improved lipophilicity and passive diffusion, promoting intracellular accumulation, while reducing toxicity and optimizing the concomitant treatment of chemo-/radiotherapy. Moreover, the blood-brain barrier (BBB) prevents the access of the drugs to the brain and accumulation in tumour cells, so it represents a key challenge for GB management. The development of novel nanomedicines with the ability to (i) encapsulate Pt-based drugs and pro-drugs, (ii) cross the BBB, and (iii) specifically target cancer cells represents a promising approach to increase the therapeutic effect of the anticancer drugs and reduce undesired side effects. In this review, a critical discussion is presented concerning different families of nanoparticles able to encapsulate platinum anticancer drugs and their application for GB treatment, emphasizing their potential for increasing the effectiveness of platinum-based drugs. Temozolomide ; Medicine ; Chemotherapy ; Prodrug ; Neurotoxicity ; Pharmacology ; Radiation therapy ; Drug ; Toxicity ; Oncology ; Internal medicine Nanoparticle-Based Drug Delivery ; Advanced biosensing and bioanalysis techniques ; Nanocluster Synthesis and Applications