jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Dibyajyoti Pathak | Naresh Aggarwal | Riya Gupta | K. V. Adarsh | Aasheesh Srivastava
Source: ChemRxiv (preprint, 2023-09-08)
Field: Chemistry — Physical and Theoretical Chemistry

Minimalistic Cationic Scaffolds Exhibiting Excited State Intramolecular Proton Transfer (ESIPT), White Light Emission and Photo-click reactions The excited state intramolecular proton transfer (ESIPT) process significantly influences the photophysics of (bio)molecules. ESIPT is facilitated by the spatial proximity of the proton donating and accepting residues as well as by the acidity of the proton being transferred. While neutral and zwitterionic molecules undergoing ESIPT are well reported in the literature, cationic scaffolds capable of ESIPT are conspicuously absent. Here, we present two cationic organic scaffolds viz. DADAB.TFA and DATzTz.TFA that exhibit rapid Anilinium-to-Azonium (Ano-Azo) ESIPT resulting in unique photophysical and photochemical outcomes. Strong 5-membered and 6-membered intramolecular hydrogen bonding (IHB) in DADAB.TFA and DATzTz.TFA, respectively, ensured the structural rigidity and planarity necessary for ESIPT. It also rendered DADAB.TFA emissive, with a moderate Stokes shift of 6597 cm-1 in H2O along with Anti-Kasha behaviour of excitation-dependent (Ex-De) emission. On the other hand, the DATzTz.TFA showed a large Stokes shift of 10209 cm-1 (in acetone). The emission of DADABH2+2 from its tautomeric azonium state gained prominence with the acidity of the protonating species. This was employed to achieve single-component white light emission (WLE) using DATzTz.TFA. Transient absorption spectroscopy (TAS) provided the lifetime of excited state absorption (ESA) as 0.85 ps for DADAB.TFA, whereas the lifetime of 1.2 ps was observed for stimulated emission (SE). Upon photoexcitation, DADAB.TFA also underwent photo-click reaction with aldehydes to yield more emissive benzimidazole frameworks. This work presents the design of new minimalistic cationic scaffolds undergoing ESIPT and expands the repertoire of photophysically-active and photochemically-reactive charged organic scaffolds. Intramolecular force ; Photochemistry ; Cationic polymerization ; Chemistry ; Hydrogen bond ; Excited state ; Proton ; Tautomer ; Stokes shift ; Molecule ; Materials science ; Luminescence ; Polymer chemistry ; Stereochemistry ; Organic chemistry ; Optoelectronics Photochemistry and Electron Transfer Studies ; Porphyrin and Phthalocyanine Chemistry ; Luminescence and Fluorescent Materials
Authors: Lijiao Wen | Zetao Shen | Xueli Cao | Chen Fan
Source: Journal of Separation Science (article, 2023-09-10)
Field: Chemistry — Analytical Chemistry

A countercurrent chromatography solvent system based on deep eutectic solvents for separation of <i>cis</i>‐ and <i>trans‐</i>crocetin from <i>Gardenia jasminoides</i> Ellis Due to the structural similarity and large difference in concentration, the separation of trans- and cis-crocetin has been challenging, and the cis-crocetin is usually neglected. In this work, a countercurrent chromatography method was developed for the quick separation of trans-crocetin and cis-crocetin from the hydrolytic extract of Gardenia jasminoides Ellis. High purity of trans-crocetin (>95%) and cis-crocetin (>91%) were prepared simultaneously for the first time through a novel biphasic system based on deep eutectic solvents, n-heptane/n-butyl alcohol/13 mmol/L Na<sub>2</sub> CO<sub>3</sub> in water/acetamide-benzyltrimethylammonium chloride (4:1, mol/mol) (4:7:9:1, v/v). The addition of deep eutectic solvent significantly improved the separation efficiency. The two targets can be easily recovered from the separation system through simple acidification and precipitation. It has potential for preparative separations on a large scale. Gardenia jasminoides ; Chromatography ; Crocetin ; Chemistry ; Countercurrent chromatography ; Deep eutectic solvent ; Solvent ; Countercurrent exchange ; Separation method ; Eutectic system ; High-performance liquid chromatography ; Organic chemistry Chromatography in Natural Products ; Saffron Plant Research Studies ; Phytochemicals and Antioxidant Activities
Authors: Nathan Sung Yuan Hsu | Angela Lin | Azalea Uva | Shine Han Huang | Helen Tran
Source: ChemRxiv (preprint, 2023-08-14)
Field: Materials Science — Polymers and Plastics

Direct Arylation Polymerization of Degradable Imine-basedConjugated Polymers The development and optimization of reliable polymerization methods are needed for the synthesis of degradable imine-based conjugated polymers, which are attractive materials for transient electronics. Direct arylation polymerization (DArP) has emerged as a sustainable and atom-economical synthetic method for the preparation of well-defined conjugated polymers. Compared to polymerization methods such as imine polycondensation or Stille cross-coupling polymerization which require monomer functionalization, direct arylation proceeds via C-H activation and thereby reduces synthetic complexities and toxic by-products. Here we report the first use of DArP for the synthesis of an imine-based indacenodithiophene (IDT) copolymer, p(IDT-TIT). Polymers prepared via DArP can result in branched or cross-linked polymer chains due to the reactivity of C-H bonds in the monomers. In this report, we demonstrate a systematic study focusing on the reaction conditions needed to prepare p(IDT-TIT) via DArP with tetramethylethylenediamine as a co-ligand. The degradable polymer is characterized via nuclear magnetic resonance spectroscopy, high-temperature gel permeation chromatography, and ultraviolet- visible-near-infrared spectroscopy. With the simplicity of monomer preparation and reaction conditions, we anticipate this efficient synthetic protocol will lead to higher synthetic adoption in the research community to aid the exploration of high-performance imine-based degradable materials. Polymerization ; Monomer ; Polymer ; Imine ; Conjugated system ; Materials science ; Polymer chemistry ; Condensation polymer ; Copolymer ; Chemistry ; Photochemistry ; Combinatorial chemistry ; Organic chemistry ; Catalysis Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Organoboron and organosilicon chemistry
Authors: Aitor Herraiz | M. P. Morales | Lydia Martínez‐Parra | Nuria Arias‐Ramos | Pilar López‐Larrubia | Lucía Gutiérrez | Jesús Mejías | Carlos Díaz‐Ufano | Jesús Ruı́z-Cabello | Fernando Herranz
Source: ChemRxiv (preprint, 2023-11-08)
Field: Materials Science — Biomaterials

Periodic table screening for enhanced positive contrast in MRI and in vivo uptake in glioblastoma The quest for nanomaterial-based imaging probes that can provide positive contrast in MRI is fueled by the necessity of developing novel diagnostic applications with potential for clinical translation that current gold standard probes cannot provide. Although interest in nanomaterials for positive contrast has increased in recent years, their study is less developed than that of traditional negative contrast probes in MRI. In our search for new magnetic materials with enhanced features as positive contrast probes for MRI, we decided to explore the chemical space to comprehensively analyze the effects of different metals on the performance of iron oxide nanomaterials already able to provide positive contrast in MRI. To this end, we synthesized 30 different iron-oxide-based nanomaterials. Thorough characterization was performed, including multivariate analysis, to study the effect of different variables on their relaxometric properties. Based on these results, we identified the best combination of metals for in vivo imaging and tested them in different experiments. First, we tested its performance on magnetic resonance angiography using a concentration ten times lower than that clinically approved for Gd. Finally, we studied the capability of these nanomaterials to cross the affected blood-brain barrier in a glioblastoma model. The results showed that the selected nanomaterials provided excellent positive contrast at large magnetic field and were able to accumulate at the tumor site, highlighting the affected tissue. Nanomaterials ; Contrast (vision) ; Magnetic resonance imaging ; In vivo ; Glioblastoma ; Materials science ; Nuclear magnetic resonance ; Biomedical engineering ; Nanotechnology ; Medicine ; Computer science ; Radiology ; Cancer research ; Artificial intelligence ; Physics ; Biology Nanoparticle-Based Drug Delivery ; Lanthanide and Transition Metal Complexes ; MRI in cancer diagnosis
Authors: Premysl Fajkus | Miroslav Mrlík | Markéta Ilčíková | Danila Gorgol | Josef Osička | Tomáš Plachý
Source: NANOCOM ... (article, 2023-01-01)
Field: Materials Science — General Materials Science

Effect of controllable modification of Srtio3 ceramic nanoparticles on piezo-active nanocomposites properties In this work the P(VDF-co-HFP) was chosen as a matrix due to the better mechanical properties compared to neat PVDF. Strontium titanate (SrTiO3) was chosen as one of the lead-free ceramics and to observe its impact of modification on nanocomposite properties. SrTiO3 nanoparticles were successfully coated with (2,2,2 triflouroethyl methacrylate) short polymer brushes using surface-initiated atom transfer radical polymerization (SI-ATRP) in order to improve the compatibility between the particles and polymer matrix. Polymer grafted from the particles surface was analyzed by gel permeation chromatography (polymer chain length and polydispersity index) and using nuclear magnetic resonance (monomer conversion). Both, neat SrTiO3 nanoparticles and their modified analogues were characterized and further compounded with poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) to obtain homogenous nanocomposites. Mechanical properties were analyzed using DMA and tensile tests. Characteristic temperatures and crystallinity were evaluated using DSC. The β-phase content was calculated using FTIR. Finally,. It was found out that modification of nanoparticles significantly enhanced the piezo-electric activity namely d33 coefficient due to the better homogeneity of the system and improved mechanical properties. Materials science ; Nanocomposite ; Ceramic ; Nanoparticle ; Composite material ; Nanotechnology ; Optoelectronics Material Properties and Applications ; Tribology and Wear Analysis ; Advancements in Materials Engineering
Authors: Yuxing Wang | Meihuizi Jiang | Saif A. Haque | Sébastien Rochat
Source: ChemRxiv (preprint, 2023-09-17)
Field: Chemistry — Physical and Theoretical Chemistry

Polymer of Intrinsic Microporosity as Light Absorber for Luminescent Solar Concentrators Luminescent solar concentrators (LSCs) hold the promise to make solar electricity more affordable by reducing the need for expensive photovoltaic cells and enabling less conventional forms of photovoltaics such as solar windows or roofs, and other architectural elements. Here we demonstrate the use of a polymer of intrinsic microporosity (PIM-1) as an efficient light absorber in an LSC, combined with a red-emitting dye. The prepared prototype LSC displays a good photoluminescence quantum yield (65.3 %) and performance metrics that show promise for the use of microporous polymers as light harvesters. This work significantly broadens the potential applications of PIMs beyond their traditional functions in molecular separations and other adsorption-based processes. Photovoltaics ; Microporous material ; Photovoltaic system ; Materials science ; Polymer ; Luminescence ; Optoelectronics ; Photoluminescence ; Quantum yield ; Nanotechnology ; Optics ; Composite material ; Physics ; Electrical engineering ; Engineering Photochemistry and Electron Transfer Studies ; Porphyrin and Phthalocyanine Chemistry ; Perovskite Materials and Applications
Authors: Baluchamy Poornasundari | Subramanian Arivoli | K. Sankarasivaraman
Source: Current Applied Science and Technology (article, 2023-06-01)
Field: Materials Science — Materials Chemistry

Investigation of Anti-hepatocarcinogenic Effects of Senna auriculata Silver Nanoparticle and Evaluation of Their Antioxidant Potential Plant-based biogenic nanoparticle synthesis has appeared as a feasible alternative to conventional approaches to chemical synthesis. As a result, several environmentally benign methods for the quick production of silver nanoparticles have been published in recent years. The methods employ aqueous extracts of plant components like leaves, bark, and roots. In the present study, silver nanoparticles were synthesized from an aqueous leaf extract of S. auriculata. UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive x-ray analysis (EDAX) were employed to validate the synthesized nanoparticles. The UV analysis showed a peak range between 390-420 nm. FTIR showed the functional groups present in the silver nanoparticles (AgNPs). Moreover, the synthesized AgNPs were tested for their antimicrobial activity against both gram-negative and gram-positive bacterial strains. The antioxidant properties were studied with DPPH, hydrogen peroxide, and nitric oxide scavenging activity assays, and a cytotoxic assay was conducted against the Huh-7 cell line by a MTT study. The results showed that the synthesized silver nanoparticles possessed strong antibacterial, antioxidant, and cytotoxic activities against the Huh-7 cell line, indicating that the silver nanoparticles might be used in the pharmaceutical industry and for novel biological applications. Silver nanoparticle ; Fourier transform infrared spectroscopy ; Nuclear chemistry ; DPPH ; Chemistry ; Nanoparticle ; Antioxidant ; Hydrogen peroxide ; Aqueous solution ; MTT assay ; Antimicrobial ; Organic chemistry ; Materials science ; Nanotechnology ; In vitro ; Biochemistry ; Chemical engineering Nanoparticles: synthesis and applications
Authors: Nathalie Zink‐Lorre | Manuel G. Ramírez | Sara Pla | Pedro G. Boj | José A. Quintana | José M. Villalvilla | Ángela Sastre‐Santos | Fernando Fernández‐Lázaro | María A. Díaz‐García
Source: Molecules (article, 2023-09-23)
Field: Materials Science — Materials Chemistry

Effect of Different Substitutions at the 1,7-Bay Positions of Perylenediimide Dyes on Their Optical and Laser Properties Perylenediimide (PDI) compounds are widely used as the active units of thin-film organic lasers. Lately, PDIs bearing two sterically hindering diphenylphenoxy groups at the 1,7-bay positions have received attention because they provide a way to red-shift the emission with respect to bay-unsubstituted PDIs, while maintaining a good amplified spontaneous emission (ASE) performance at high doping rates. Here, we report the synthesis of a series of six PDI derivatives with different aryloxy groups (<b>PDI 6</b> to <b>PDI 10</b>) or ethoxy groups (<b>PDI 11</b>) at the 1,7 positions of the PDI core, together with a complete characterization of their optical properties, including absorption, photoluminescence, and ASE. We aim to stablish structure-property relationships that help designing compounds with optimized ASE performance. Film experiments were accomplished at low PDI concentrations in the film, to resemble the isolated molecule behaviour, and at a range of increasing doping rates, to investigate concentration quenching effects. Compounds <b>PDI 10</b> and <b>PDI 7</b>, bearing substituents in the 2' positions of the benzene ring (the one contiguous to the linking oxygen atom) attached to the 1,7 positions of the PDI core, have shown a better threshold performance, which is attributed to conformational (steric) effects. Films containing <b>PDI 11</b> show dual ASE. Steric effects ; Alkoxy group ; Photoluminescence ; Doping ; Quenching (fluorescence) ; Benzene ; Molecule ; Chemistry ; Photochemistry ; Amplified spontaneous emission ; Absorption (acoustics) ; Materials science ; Laser ; Stereochemistry ; Organic chemistry ; Fluorescence ; Optoelectronics ; Optics ; Alkyl Luminescence and Fluorescent Materials ; Photochemistry and Electron Transfer Studies ; Nonlinear Optical Materials Studies
Authors: Xuan Liang | Shan Qian | Zhizheng Lou | HU Ren-ming | Yu‐Chen Hou | Peng R. Chen | Xinyuan Fan
Source: ChemRxiv (preprint, 2023-10-17)
Field: Chemistry — Organic Chemistry

Near Infrared Light-Triggered Photocatalytic Decaging for Remote-Controlled Spatiotemporal Activation in Living Mice Spatiotemporal manipulation of biological processes in living animals using noninvasive, remote-controlled stimuli is a capti-vating but challenging endeavor. Herein, we present the development of a biocompatible photocatalytic technology termed CAT-NIR, which uses external near infrared light (NIR, 740 nm) to trigger decaging reactions in living mice. The Os(II) terpyridine complex was identified as an efficient NIR photocatalyst for promoting deboronative hydroxylation reactions via superoxide generation in the presence of NIR light, resulting in the deprotection of phenol groups and the release of bioactive molecules under living conditions. The validation of the CAT-NIR system was demonstrated through the NIR-triggered rescue of fluorophores, prodrugs as well as biomolecules ranging from amino acids, peptides to proteins. Furthermore, by combining genetic code expansion and computer-aided screening, CAT-NIR could regulate affibody binding to the cell surface receptor HER2, providing a selective cell tagging technology through external NIR light. In particular, the tissue-penetrating ability of NIR light allowed for facile prodrug activation in living mice, enabling noninvasive, remote-controlled rescue of drug molecules. Given its broad adaptability, this CAT-NIR system may open new opportunities for manipulating the functions of bioactive molecules in living animals using external NIR light with spatiotemporal resolution. Biomolecule ; Small molecule ; Prodrug ; Near-infrared spectroscopy ; Chemistry ; Photocatalysis ; Biocompatible material ; Nanotechnology ; Biophysics ; Combinatorial chemistry ; Materials science ; Biochemistry ; Catalysis ; Biomedical engineering ; Biology Click Chemistry and Applications ; Nanoplatforms for cancer theranostics
Authors: Kevin Castillo | Aaron Tasset | Milos Marinkovic | Aaron Foote
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2023-06-08)
Field: Materials Science — Materials Chemistry

Discrete Multiwalled Carbon Nanotubes for Versatile Intracellular Transport of Functional Biomolecular Complexes Abstract In recent years, carbon nanotubes have emerged as a potentially revolutionary material with numerous uses in biomedical applications. Compared to other nanoparticles, discrete multi-walled carbon nanotubes (dMWCNTs) have been shown to exhibit advantageous characteristics such as high surface area to volume ratio, biocompatibility, and unique chemical and physical properties. dMWCNTs can be modified to load various molecules such as proteins and nucleic acids and are capable of crossing the cell membrane, making them attractive delivery vehicles for biomolecules. To investigate this, we measured the impact of dMWCNTs on cell proliferation. Furthermore, we used electron microscopy to demonstrate that dMWCNTs enter the cytoplasm of mammalian cells via an endocytosis-like process. And lastly, we employed various in vitro reporter and gene assays to demonstrate dMWCNT-mediated delivery of peptides, mRNA, siRNA, and dsRNA. Our work here has helped further characterize dMWCNTs as a versatile delivery platform for biomolecular cargo. Biomolecule ; Nanotechnology ; Carbon nanotube ; Cytoplasm ; Biocompatibility ; Endocytosis ; Nucleic acid ; Gene delivery ; Intracellular ; Materials science ; Biophysics ; Membrane ; Cell ; Chemistry ; Transfection ; Biology ; Biochemistry ; Gene Carbon Nanotubes in Composites ; Graphene and Nanomaterials Applications ; Advanced biosensing and bioanalysis techniques
Authors: Caterina Damiano | Matteo Cavalleri | Corrado Di Natale | Roberto Paolesse | Emma Gallo
Source: ChemistryEurope (article, 2023-05-05)
Field: Materials Science — Materials Chemistry

Porphyrins Anchored onto Colour Catcher®: Photoactive Material for the Conversion of Amines into Imines and Aldehydes into Carboxylic Acids Abstract A new photoactive material was obtained by the heterogenization of zinc(II) porphyrin onto cellulose‐based Colour Catcher® sheet. The so‐obtained Zn(porphyrin)@CC material performed very well in activating molecular oxygen in the photooxidative coupling of amines to imines and the photooxidation of aldehydes to corresponding acids in the presence of white light. The high eco‐compatibility of the solid support, the chemical stability of the photoactive material and the mild experimental conditions applied confer a very good sustainability to the procedure and open the doors to a larger employment of Colour Catcher®‐based porphyrin material in reactions mediated by light. Porphyrin ; Chemistry ; Zinc ; Photochemistry ; Organic chemistry ; Polymer chemistry Porphyrin and Phthalocyanine Chemistry ; Radical Photochemical Reactions ; Oxidative Organic Chemistry Reactions
Authors: Feng Mengdie | Yonghua Zheng
Source: Biomaterials and Biosensors (article, 2023-10-09)
Field: Materials Science — Biomaterials

Advances in the use of cell-membrane encapsulated nanoparticles to target tumor drugs &lt;p style="text-align: justify;"&gt;Cancer treatment faces multiple challenges, including tumor heterogeneity, drug resistance, microenvironment influence, treatment side effects, and treatment cost. The heterogeneity of the tumor makes the effect of the same treatment vary in different patients, so the development of personalized treatment strategies is crucial. In addition, resistance of tumor cells to therapeutic drugs is a major challenge, and new strategies to overcome resistance are needed. As a cutting-edge field of science and technology, nanotechnology has brought great potential and opportunities for tumor treatment. Nanoparticle drug delivery systems improve drug efficacy and reduce side effects through precise targeted delivery and controlled release. Cell-membrane coated nanoparticles show great promise in tumor therapy. Nanoparticles coated with cell membranes have good biocompatibility, can reduce the obstacles of immune rejection and cell uptake, improve the accumulation and retention of drugs in tumor tissues, and have good drug delivery ability, drug stability and control release ability. This review discusses advances in the use of cell-membrane coated nanoparticles to target tumor drugs.&lt;/p&gt; Drug delivery ; Tumor microenvironment ; Drug resistance ; Drug ; Cell ; Nanotechnology ; Cancer cell ; Biocompatibility ; Cancer research ; Tumor cells ; Medicine ; Cancer ; Chemistry ; Materials science ; Pharmacology ; Biology ; Internal medicine Nanoparticle-Based Drug Delivery ; Nanoplatforms for cancer theranostics ; RNA Interference and Gene Delivery