jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Himanshi Soni | Jasmeen Kaur | Roberto Acevado | Meenakshi Verma
Source: E3S Web of Conferences (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Green synthesis of carbon dots for sensing of heavy metal ions: Bibliometric analysis from 2003-2024 The release of heavy metals into the environment has surged, due to rapid industrialization and urbanization globally, which causes. contamination of air, water, and soil. These persistent and bioaccumulative metals (lead, mercury, cadmium, and arsenic) pose major risks to both human health and the ecological balance. Therefore, heavy metal pollution emerges as a daunting challenge in contemporary times, Carbon dots (CDs) have attracted significant attention in recent years due to their potential applications in sensing heavy metal ions. Many conventional chemical methods have been used for the synthesis of CDs, however, these methods possess many shortcomings such as noxious byproducts, harsh chemicals, high cost, etc. To diminish these shortcomings, green chemistry plays a significant role in the preparation of CDs. Thus, it is very imperative to explore the green synthesis methodologies for the preparation of CDs over conventional ones. The article delves into a comprehensive bibliometric analysis of the green synthesis methods CDs for heavy metal ion sensing applications in the period between 2003-2024. Additionally, we have also provided an overview of the mechanism behind the green synthesis of CDs by exploring the role of phytoconstitutes present in natural resources. Furthermore, the sensing mechanism of CDs toward heavy metal ions is also explored. This review compiles the bibliometric analysis and synthesis process with various materials used for the detection of heavy metals. Carbon fibers ; Metal ions in aqueous solution ; Metal ; Nanotechnology ; Environmental science ; Materials science ; Environmental chemistry ; Metallurgy ; Chemistry ; Composite material Carbon and Quantum Dots Applications ; Advanced biosensing and bioanalysis techniques ; Nanocluster Synthesis and Applications
Authors: Manisha M Patil | Aejaz A A Rafique
Source: International Journal of Pharmaceutical Sciences and Drug Research (article, 2024-07-30)
Field: Chemistry — Analytical Chemistry

Box-Behnken Design employed stability demonstrating RP-HPLC method development of sorafenib tosylate for rapid and sensitive quantification Sorafenib tosylate (SFN) is a tyrosine kinase inhibitor used clinically to treat liver, kidney, and thyroid carcinoma. This research aims to accurately quantify SFN using a quality-by-design (QbD) approach with RP-HPLC. Chromatographic settings were optimized using a Box-Behnken design, measuring responses such as retention time, tailing factor, theoretical plate, and peak area. At the same time, independent variables were flow rate, mobile phase composition, and wavelength. A C18 column (4.6 × 250 mm, 5 µm) served as the stationary phase, with a mobile phase of methanol and 0.1% o-phosphoric acid in a 41:59 v/v ratio. SFN detection occurred at 267 nm in isocratic mode at a flow rate of 1.1 mL min−1. Method validation followed International Council for Harmonization guidelines, yielding a coefficient of determination (R2) of 0.9998, indicating linearity in the 5-25 µg mL−1 range. Results showed detection (LOD) and quantification (LOQ) limits of 0.04 and 0.12 µg mL−1, respectively. Additionally, the method demonstrated precision, accuracy, and robustness consistent with ICH criteria. Overall, this simple, accurate, rapid, and robust RP-HPLC method is suitable for routine SFN analysis in various formulations. Box–Behnken design ; Chromatography ; Chemistry ; Response surface methodology Analytical Methods in Pharmaceuticals ; Inorganic and Organometallic Chemistry
Authors: Vladyslav Smyrnov | Antonin Homassel | Leander Choudhury | Jérôme Waser
Source: Helvetica Chimica Acta (article, 2024-07-05)
Field: Chemistry — Organic Chemistry

Platinum‐Catalyzed Isomerization of Cyclopropenes to 1,3‐Dienes Abstract Herein we report a platinum‐catalyzed isomerization of cyclopropenes to 1,3‐dienes. Diverse dienylated alcohols were obtained in 42–98 % yield. The synthetic potential of the products was demonstrated by their use in Diels–Alder cycloadditions with various dienophiles. Isotope labelling studies provide strong support for a mechanism involving pericyclic [1,5]‐σ‐bond rearrangement of a vinyl platinum carbene intermediate. Chemistry ; Isomerization ; Catalysis ; Platinum ; Photochemistry ; Medicinal chemistry ; Organic chemistry Cyclopropane Reaction Mechanisms ; Catalytic Alkyne Reactions ; Synthetic Organic Chemistry Methods
Authors: Silvio Jakopec | Natalija Pantalon Juraj | Dijana Jadreško | Robert Vianello | Anamaria Brozović | Vanja Tadić | Lea Milić | Berislav Perić | Silvana Raić‐Malić | Srećko I. Kirin
Source: Applied Organometallic Chemistry (article, 2024-03-17)
Field: Chemistry — Organic Chemistry

Late transition metal complexes of ferrocene‐containing nitrogen ligands: Coordination chemistry, electron transfer properties, and tumor cell viability Bis(2‐picolyl)amine (bpa), iminodiacetamide (imda), and bis‐1,2,3‐triazole (bta) ferrocene ligands (L) with and without an aliphatic linker were prepared by multi‐step synthesis. The cis‐fac , trans‐fac , or mer stereochemistry of their ML 2 complexes with Ni(II), Cu(II), Cd(II), and Zn(II) was studied in the solid state (infrared [IR] and single‐crystal X‐ray diffraction [SC‐XRD]), in solution (nuclear magnetic resonance [NMR] and cyclic voltammetry [CV]) and by density functional theory (DFT) calculations. Crystal structures were determined for bpa ligand 7 , and complexes [Ni( 1 ) 2 ](NO 3 ) 2 ( 1 Ni ), [Cu( 8 ) 2 ]OTf 2 ( 8 Cu ), [Ni( 10b ) 2 ](NO 3 ) 2 ( 10b Ni ), and [Cu( 10b ) 2 ]OTf 2 ( 10b Cu ). The bond strength of the central metal ion to the ligand amine nitrogen atom was studied by NMR, electrochemistry, and DFT. The information on redox‐active centers, electron transfer properties of ferrocene ligands (L), and their in situ complexation with zinc(II) and nickel(II) ions were obtained by voltammetric analysis. In addition, DFT calculations showed that the electron ionization in ML 2 complexes occurs from one of the ferrocene units, leaving the electronic structure of the other ligand intact, while some of the expelled electron density is recovered by the adjacent amine through resonance. This effect is more pronounced in the free ligands, because the eventual amine resonance in ML 2 needs to balance its Zn(II) coordination participation, which justifies why they show higher ionization energies over free ligands. Moreover, due to lower steric hindrance, the N(amino)–Zn(II) coordination is additionally stronger in 1:1 ML complexes, which makes their electron depletion further more demanding. If compared with the clinical drug cisplatin, complexes of bpa 1 Ni and imda 2 Ni showed a better effect on the viability of different tumor cell lines and better selectivity towards normal cells. Treatment with 1 Ni and 2 Ni causes an increase of cells in the S phase of the cell cycle and leads to the accumulation of cells in G 0 /G 1 . A decrease in the expression level of anti‐apoptotic marker Bcl‐2 upon treatment with both compounds together with increased amount of Annexin V‐FITC positive cells implied apoptosis as the mode of cell death. Chemistry ; Ferrocene ; Transition metal ; Electron transfer ; Coordination complex ; Nitrogen ; Metal ; Polymer chemistry ; Photochemistry ; Organic chemistry ; Physical chemistry ; Catalysis ; Electrochemistry Ferrocene Chemistry and Applications ; Metal complexes synthesis and properties ; Synthesis and Biological Evaluation
Authors: Zhen Lei | Ksenya Mull | Nikolay Dimitrov
Source: Journal of The Electrochemical Society (article, 2024-08-29)
Field: Materials Science — Materials Chemistry

New Electrochemical Approach for Synthesis of Nanoporous Silver Cu-Ag alloy films were electrodeposited on Au substrates to serve as precursor alloys for synthesizing finely-structured nanoporous Ag (NPS) structures. Two innovative approaches, surface limited redox replacement (SLRR) and defect mediated growth (DMG) along with overpotential deposition (OPD), were comparatively utilized to fabricate Cu-Ag alloy films. The electrolyte for these novel approaches contained Pb 2+ ions to serve either as a sacrificial metal to be replaced by the co-depositing Cu and Ag (in SLRR) or as mediating metal to facilitate the 2D growth of both alloy constituents (in DMG). The resulting alloy films from both approaches displayed superior uniformity and miscibility compared to the OPD alloy, as evidenced by electrochemical scanning electron microscopy (SEM) and X-ray diffraction characterization routines. In a subsequent step, NPS structures were generated through the de-alloying of as-deposited Cu-Ag alloys, as illustrated by SEM imaging that revealed ligament and pore sizes with a thickness in the ballpark of 40 nm. Also, surface area measurements done by a Pb underpotential deposition assay suggested a surface enhancement ratio nearly five times higher than that of flat Ag. Furthermore, various de-alloying potentials were assessed to determine the optimal de-alloying potential for the best outcome of the de-alloying process. Nanoporous ; Electrochemistry ; Materials science ; Nanotechnology ; Chemical engineering ; Chemistry ; Electrode ; Physical chemistry ; Engineering Nanoporous metals and alloys ; Electrocatalysts for Energy Conversion ; Anodic Oxide Films and Nanostructures
Authors: Jinghui Cheng | Yi Li | Zhiye Zhu | Huijuan Guan | Jing Zhai | Yong‐Bing Xiang | Man Wang
Source: Molecules (article, 2024-12-11)
Field: Chemistry — Spectroscopy

A Simple and Rapid “Turn-On” Fluorescent Probe Based on Binuclear Schiff Base for Zn2+ and Its Application in Cell Imaging and Test Strips A series of colorful binuclear Schiff bases derived from the different diamine bridges including 1,2- ethylenediamine (bis-Et-SA, bis-Et-4-NEt<sub>2</sub>, bis-Et-5-NO<sub>2</sub>, bis-Et-Naph), 1,2-phenylenediamine (bis-Ph-SA, bis-Ph-4-NEt<sub>2</sub>, bis-Ph-5-NO<sub>2</sub>, bis-Ph-Naph), dicyano-1,2-ethenediamine (bis-CN-SA, bis-CN-4-NEt<sub>2</sub>, bis-CN-5-NO<sub>2</sub>, bis-CN-Naph) have been designed and prepared. The optical properties of these binuclear Schiff base ligands were fully determined by UV-Vis absorption spectroscopy, fluorescence emission spectroscopy, and time-dependent-density functional theory (TD-DFT) calculations. The inclusion of D-A systems and/or π-extended systems in these binuclear Schiff base ligands not only enables adjustable RGB light absorption and emission spectra (300~700 nm) but also yields high fluorescence quantum efficiencies of up to 0.84 in MeCN solution. Then, with the ESIPT (excited-state intramolecular proton transfer) property, fluorescence analysis showed that the probe bis-Et-SA and bis-Ph-SA could recognize Zn<sup>2+</sup> via the "turn on" mode in the MeCN solution. During the detection process, bis-Et-SA and bis-Ph-SA demonstrate rapid response and high selectivity upon the addition of Zn<sup>2+</sup>. The coordination of Zn<sup>2+</sup> with the oxygen atom and Schiff base nitrogen atom in a tetrahedral geometry is confirmed by Job's plot, FT-IR, and <sup>1</sup>H NMR spectroscopy. In addition, the paper test and Hela cells were successfully carried out to detect Zn<sup>2+</sup>. Moreover, the sensitivity of bis-Et-SA and bis-Ph-SA is much better than that of those Schiff base ligands containing only one chelating unit [O^N^N^O]. Schiff base ; Chemistry ; Fluorescence ; Intramolecular force ; Ethylenediamine ; Proton NMR ; Naked eye ; Absorption spectroscopy ; Photochemistry ; Fluorescence spectroscopy ; Spectroscopy ; Absorption (acoustics) ; Excited state ; Detection limit ; Crystallography ; Stereochemistry ; Inorganic chemistry ; Materials science Molecular Sensors and Ion Detection ; Metal complexes synthesis and properties ; Luminescence and Fluorescent Materials
Authors: Jie Wang | Irán Rojas‐León | Niklas Rinn | Lukas Guggolz | Ferdinand Ziese | Simone Sanna | Nils W. Rosemann | Stefanie Dehnen
Source: Angewandte Chemie (article, 2024-08-19)
Field: Chemistry — Organic Chemistry

Strain‐Induced Structural Rearrangement Towards a White‐Light‐Emitting Adamantane‐Type Cluster Dimer Abstract Group 14/16 adamantane‐type hybrid clusters of the type [(RT) 4 E 6 ] (T=group 14 element, E=group 16 element, R=organic group) have been reported to emit white‐light when irradiated in an amorphous state with a continuous‐wave (CW) infrared laser diode. This effect is enhanced if the cluster core is varied from a binary to a more complex composition. To further explore this phenomenon, we synthesized clusters with a multinary R/R’‐T/T’‐E/E’ composition, including isolobal replacement of E with CH 2 , in [(2‐NpSi){CH 2 Sn(S)Ph} 3 ] ( 1 , Np=naphthyl). When expanding one of the CH 2 moieties to a C 2 H 4 group, thus generating a R/R’‐T/T’‐E/E’/E’’ cluster composition, we unexpectedly observed a dimerization of the initially formed, yet non‐isolable adamantane‐like cluster [(2‐NpSi){CH 2 Sn(S)Ph} 2 {C 2 H 4 Sn(S)Ph}] ( 2 ) to [(2‐NpSi){CH 2 Sn(S)Ph} 2 {C 2 H 4 Sn(S)Ph}] 2 ( 3 ), exhibiting a heretofore unprecedented cluster architecture. Both monomeric 1 and dimeric 3 , show white‐light emission as thin films. The nonlinear optical response of the compounds was also modelled with DFT methods. Adamantane ; Dimer ; Crystallography ; Cluster (spacecraft) ; Chemistry ; Stereochemistry ; Monomer ; Strain (injury) ; Photochemistry ; Materials science ; Polymer ; Organic chemistry Organometallic Compounds Synthesis and Characterization ; Nonlinear Optical Materials Research ; Crystal structures of chemical compounds
Authors: Arwa Abdo | Hend Mostafa | Tarek Wahdan | Zeinab M. Anwar
Source: Egyptian Journal of Chemistry (article, 2024-03-20)
Field: Chemistry — Analytical Chemistry

Spectrophotometric Estimation of Donepezil Hydrochloride in pure and dosage forms via ion-pair complex with Erythrosine Dye. In this study, the goal is to improve and verify a simple, sensitive, accurate spectrophotometric technique for the measurement of drug formulations and pure forms of donepezil HCl (DNP). The procedure is forming an ion-pair complex in an acetate buffer solution between donepezil and the dye erythrosine B. The resulting complex is then measured spectrophotometrically at a wavelength of maximum absorbance (λ max) of 527nm. Beer's law was found to be applicable in the concentration range of 0.2-1.2 mg/ml, with a high correlation coefficient (n=5) of 0.99813. This indicates a strong linear relationship between the concentration of Donepezil HCl and the absorbance values within the specified range. The limit of detection (LOD) for the drug was determined to be 0.95056 mg/ml, representing the lowest concentration at which the method can reliably detect the presence of Donepezil HCl. Additionally, the limit of quantification (LOQ) was established at 3.1685 mg/ml, indicating the lowest concentration at which accurate quantification can be achieved. The proposed method was subjected to validation for accuracy and precision, demonstrating its reliability and reproducibility. The developed spectrophotometric method has been successfully applied to the analysis of Donepezil in its pure form as well as in pharmaceutical dosage form Erythrosine ; Donepezil ; Hydrochloride ; Chemistry ; Chromatography ; Medicine ; Organic chemistry ; Internal medicine ; Dementia Analytical Methods in Pharmaceuticals ; Analytical Chemistry and Chromatography ; Analytical Chemistry and Sensors
Authors: Griffin C. Spence | D. Pate | Corentin Villot | Roshana M Fouzie | Lisa S. Graves | Ka Un Lao | Ü. Özgür | Indika U. Arachchige
Source: Nanoscale (article, 2024-12-04)
Field: Materials Science — Materials Chemistry

Solid-state synthesis of Si<sub>1−<i>x</i></sub>Ge<sub><i>x</i></sub> nanoalloys with composition-tunable energy gaps and visible to near infrared optical properties Si<sub>1-<i>x</i></sub>Ge<sub><i>x</i></sub> alloy nanocrystals (NCs) are a class of benign semiconductors that show size and composition-tunable energy gaps and promising optical properties because of the lattice disorder. The random distribution of elements within the alloys can lead to efficient light-matter interactions, making them attractive for Si-compatible optoelectronic devices, transistors, charge storage, and memory applications. However, the fabrication of discrete, quantum-confined alloys has proved a challenging task. Herein, we report solid-state co-disproportionation of a hydrogen silsesquioxane (HSQ)/GeI<sub>2</sub> composite precursor to produce homogeneous Si<sub>1-<i>x</i></sub>Ge<sub><i>x</i></sub> NCs with control over the diameter (5.9 ± 0.7-7.8 ± 1.1 nm) and composition (<i>x</i> = 0-14.4%) with strong size confinement effects and visible to near IR absorption and emission properties. As-synthesized alloys show an expanded diamond cubic Si structure, a systematic red-shift of Si-Si Raman peak, and emergence of Si-Ge/Ge-Ge peaks with increasing Ge, consistent with the admixture of isovalent elements. Surface analysis of alloys reveals Si<sup>0</sup>/Ge<sup>0</sup> core and Si<sup><i>n</i>+</sup>/Ge<sup><i>n</i>+</sup> surface species and efficient surface functionalization with alkyl ligands <i>via</i> thermal hydrosilylation and/or hydrogermylation. Alloy NCs exhibit absorption onsets (2.26-1.92 eV), indirect (1.53-1.80 eV) and direct (2.88-2.47 eV) energy gaps, and photoluminescence (PL) maxima (1.40-1.27 eV) that can be tuned by manipulating the diameter and/or composition. The experimental PL energies are consistent with those predicted by density functional theory (DFT), suggesting that the PL originates from NC core electronic transitions. The facile low-temperature solid-state synthesis and control over physical properties realized in this study will allow discrete Si<sub>1-<i>x</i></sub>Ge<sub><i>x</i></sub> NCs to emerge as low to nontoxic, earth-abundant, and Si-compatible nanostructures for a broad range of electronic and photonic technologies. Infrared ; Materials science ; Solid-state ; Composition (language) ; Band gap ; Energy (signal processing) ; Visible spectrum ; Optoelectronics ; State (computer science) ; Physical chemistry ; Chemistry ; Optics ; Physics Silicon Nanostructures and Photoluminescence ; Semiconductor materials and interfaces ; Nanowire Synthesis and Applications
Authors: Himanshi Awasthi | Pavar Sai Kumar | Thomas Thundat | Sanket Goel
Source: Advanced Energy and Sustainability Research (article, 2024-10-28)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Flexible Supercapacitor Device Based on Laser‐Synthesized Nanographene for Low‐Power Applications Laser‐induced graphene (LIG) and laser‐induced reduced graphene oxide (LIrGO) are two relatively recent graphene‐based nanoscale materials suitable for miniaturized flexible supercapacitors. This study employs direct laser engraving techniques to generate patterns on flexible substrates, such as paper and polyamide (PI). This methodology allows fine control over the formed nanographene structures to fabricated LIG and LIrGO supercapacitors. The LIG on PI exhibits a distinctive porous structure and high surface area, adsorption, and transportation of ions. Furthermore, paper‐based LIrGO electrodes are recyclable and are formed in a single step. The morphological study is done using scanning electron microscopy, Raman spectroscopy, X‐ray photoelectron spectroscopy, and X‐ray diffraction. Galvanostatic charge–discharge studies at 0.05 mA cm −2 current density show an areal capacitance of 3.69 mF cm −2 for LIG and 1.61 mF cm −2 for LIrGO. The comparable energy densities for LIG and LIrGO are 0.32 and 0.16 μWh cm −2 , respectively. From the calculative analysis of both types, the variation in specific areal capacitance enabling effective is 56.3% from GCD, indicating that the LIG device performs better. Finally, a portable potentiostat is employed to investigate the viability of utilizing supercapacitors to operate self‐powered sensors in a portable and integrable fashion. Supercapacitor ; Materials science ; Laser ; Power (physics) ; Optoelectronics ; Nanotechnology ; Capacitance ; Optics ; Electrode ; Chemistry ; Physics Supercapacitor Materials and Fabrication ; Laser-Ablation Synthesis of Nanoparticles ; Graphene research and applications
Authors: Carla Arnau del Valle | Paul Thomas | Francisco Galindo | Maria Paz Munoz-Herranz | María J. Marín
Source: Photodiagnosis and Photodynamic Therapy (article, 2024-04-01)
Field: Materials Science — Materials Chemistry

Gold nanoparticle-based two-photon fluorescent nanoprobe for monitoring intracellular nitric oxide levels Nitric oxide (NO) is involved in the regulation of physiological and pathological mechanisms of the cardiovascular, nervous and immune systems; and plays an important role in cancer being involved in tumor growth and suppressing processes depending on its concentration. The development of a near-infrared excitable nanoprobe, consisting of gold nanoparticles functionalized with a two-photon excitable NO probe, for the detection of intracellular NO is reported. The nanoprobe showed good selectivity towards NO over cellular interferences and excellent stability in aqueous-medium over time. The nanoprobe was able to selectively detect endogenous and exogenous NO in different cell lines and it accumulated in the acidic organelles showing negligible toxicity. Importantly, the nanoprobe showed potential to quantify intracellular NO concentrations in breast cancer cells. The novel gold-based two-photon nanoprobe showed an excellent performance and versatility and could potentially be applied for the spatiotemporal monitoring of in vivo NO levels. Nanoprobe ; Fluorescence ; Intracellular ; Nitric oxide ; Colloidal gold ; Nanoparticle ; Photon ; Two-photon excitation microscopy ; Nanotechnology ; Materials science ; Chemistry ; Photochemistry ; Biophysics ; Optics ; Biochemistry ; Biology ; Physics ; Organic chemistry Advanced Nanomaterials in Catalysis ; Electrochemical sensors and biosensors ; Molecular Sensors and Ion Detection
Authors: Xiaoyu Zhang | Lin Wei | Jiezhen Liu | Jiangwen Liu | Can Weng
Source: Polymers (article, 2024-06-06)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Tuning Electro-Optical Characteristics through Polymerization Monomer Content in PSVA Liquid Crystal Displays: Simulation and Experimentation The enhancement of display performance and durability in polymer-stabilized vertical alignment liquid crystal and the liquid crystal are negative liquid crystals, which can be vertically aligned under the action of a vertical orientation layer and an electric field. Devices (PSVA LCDs) are crucial for advancing LCD technology. This study aims to investigate the electro-optical characteristics of PSVA LCDs by varying polymerization monomer concentrations. Using both simulations via TechWiz LCD 3D and experimental methods, such as polymer-induced phase separation, we developed an optoelectronic testing framework to assess voltage transmittance and response times. In our main findings, we show that an increase in polymeric monomer concentration from 3% to 7% resulted in a 67% increase in threshold voltage and a 44% decrease in saturation voltage. The on-state response time increased by about a factor of three, while the off-state response time decreased by about a factor of three. The alignment of our simulation results with experimental data validates our methodology, offering the potential of simulation tools as a pivotal resource in the PSVA LCDs. The alignment of our simulation results with experimental data validates our methodology, offering the potential of simulation tools as a pivotal resource in the PSVA LCDs. These advancements promise significant improvements in PSVA LCD performance and durability. Materials science ; Liquid-crystal display ; Liquid crystal ; Viewing angle ; Voltage ; Polymer ; Polymerization ; Monomer ; Durability ; Transmittance ; Optoelectronics ; Electric field ; Composite material ; Electrical engineering ; Engineering Liquid Crystal Research Advancements ; Semiconductor Lasers and Optical Devices ; Photonic and Optical Devices