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981.
Ratnadip De Prof. Dr. Benjamin Dietzek-Ivanšić 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(55):e202200407
Electrochemical interfaces are key structures in energy storage and catalysis. Hence, a molecular understanding of the active sites at these interfaces, their solvation, the structure of adsorbates, and the formation of solid-electrolyte interfaces are crucial for an in-depth mechanistic understanding of their function. Vibrational sum-frequency generation (VSFG) spectroscopy has emerged as an operando spectroscopic technique to monitor complex electrochemical interfaces due to its intrinsic interface sensitivity and chemical specificity. Thus, this review discusses the happy get-together between VSFG spectroscopy and electrochemical interfaces. Methodological approaches for answering core issues associated with the behavior of adsorbates on electrodes, the structure of solvent adlayers, the transient formation of reaction intermediates, and the emergence of solid electrolyte interphase in battery research are assessed to provide a critical inventory of highly promising avenues to bring optical spectroscopy to use in modern material research in energy conversion and storage. 相似文献
982.
Andrea Mosseri Dr. Maria Sancho-Albero Dr. Marilisa Leone Donatella Nava Dr. Francesco Secundo Prof. Daniela Maggioni Prof. Luisa De Cola Prof. Alessandra Romanelli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(37):e202200693
Self-assembly of biomolecules such as peptides, nucleic acids or their analogues affords supramolecular objects, exhibiting structures and physical properties dependent on the amino-acid or nucleobase composition. Conjugation of the peptide diphenylalanine (FF) to peptide nucleic acids triggers formation of self-assembled structures, mainly stabilized by interactions between FF. In this work we report formation of homogeneous chiral fibers upon self-assembly of the hybrid composed of the tetraphenylalanine peptide (4F) conjugated to the PNA dimer adenine-thymine (at). In this case nucleobases seem to play a key role in determining the morphology and chirality of the fibers. When the PNA “at” is replaced by guanine-cytosine dimer “gc”, disordered structures are observed. Spectroscopic characterization of the self-assembled hybrids, along with AFM and SEM studies is reported. Finally, a structural model consistent with the experimental evidence has also been obtained, showing how the building blocks of 4Fat arrange to give helical fibers. 相似文献
983.
A. Privitera L. Ruggiero I. Venditti U. Pasqual Laverdura S. Tuti D. De Felicis S. Lo Mastro L. Duranti E. Di Bartolomeo T. Gasperi M.A. Ricci A. Sodo 《Materials Today Chemistry》2022
The direct application of corrosion inhibitors on metal surfaces is potentially dangerous for the environment and the restoration operators, thus new conservation strategies are mandatory. In this study, two copper corrosion inhibitors, 1H-benzotriazole (BTA) and 5-phenyl-1H-tetrazole (PT), are encapsulated in a silica nanocontainer, for future application in smart coatings, with the aim to reduce the amount of chemicals used in treatments, their dispersion in the environment and the direct exposure of the operators to these chemicals. In particular, composite silica nanocapsules, containing the corrosion inhibitors, are prepared via one-step synthesis, based on mini-emulsion polymerisation processes.The morphology, structure, and texture of these loaded silica nanocontainers are characterised by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2 physisorption (BET/BJH). Micro-Raman spectroscopy (RS) is performed to characterise the composition. UV–visible spectroscopy and thermal analysis (TG/DSC) are performed for the loading and encapsulation efficiency (L%, EE%) study.Synthesised nanocapsules show a core-shell structure and, when loaded with the inhibitors, have size ranging from about 130 to 170 nm and a BET surface area of the order of 800 m2/g. The EE% is maximum in the case of BTA and decreases to ~52% in the case of PT. 相似文献
984.
Prof. Gianlorenzo Bussetti Claudia Filoni Prof. Andrea Li Bassi Dr. Alberto Bossi Prof. Marcello Campione Prof. Alessio Orbelli Biroli Prof. Chiara Castiglioni Dr. Silvia Trabattoni Dr. Stefania De Rosa Prof. Luca Tortora Prof. Franco Ciccacci Prof. Lamberto Duò 《ChemistryOpen》2021,10(8):748-755
We have recently discussed how organic nanocrystal dissolution appears in different morphologies and the role of the solution pH in the crystal detriment process. We also highlighted the role of the local molecular chemistry in porphyrin nanocrystals having comparable structures: in water-based acid solutions, protonation of free-base porphyrin molecules is the driving force for crystal dissolution, whereas metal (ZnII) porphyrin nanocrystals remain unperturbed. However, all porphyrin types, having an electron rich π-structure, can be electrochemically oxidized. In this scenario, a key question is: does electrochemistry represent a viable strategy to drive the dissolution of both free-base and metal porphyrin nanocrystals? In this work, by exploiting electrochemical atomic force microscopy (EC-AFM), we monitor in situ and in real time the dissolution of both free-base and metal porphyrin nanocrystals, as soon as molecules reach the oxidation potential, showing different regimes according to the applied EC potential. 相似文献
985.
Jesús G. Zorrilla Carlos Rial Daniel Cabrera Jos M. G. Molinillo Rosa M. Varela Francisco A. Macías 《Molecules (Basel, Switzerland)》2021,26(11)
Aminophenoxazinones are degradation products resulting from the metabolism of different plant species, which comprise a family of natural products well known for their pharmacological activities. This review provides an overview of the pharmacological properties and applications proved by these compounds and their structural derivatives during 2000–2021. The bibliography was selected according to our purpose from the references obtained in a SciFinder database search for the Phx-3 structure (the base molecule of the aminophenoxazinones). Compounds Phx-1 and Phx-3 are among the most studied, especially as anticancer drugs for the treatment of gastric and colon cancer, glioblastoma and melanoma, among others types of relevant cancers. The main information available in the literature about their mechanisms is also described. Similarly, antibacterial, antifungal, antiviral and antiparasitic activities are presented, including species related directly or indirectly to significant diseases. Therefore, we present diverse compounds based on aminophenoxazinones with high potential as drugs, considering their levels of activity and few adverse effects. 相似文献
986.
Lucia De Rosa Rossella Di Stasi Alessandra Romanelli Luca Domenico DAndrea 《Molecules (Basel, Switzerland)》2021,26(12)
Although a plethora of chemistries have been developed to selectively decorate protein molecules, novel strategies continue to be reported with the final aim of improving selectivity and mildness of the reaction conditions, preserve protein integrity, and fulfill all the increasing requirements of the modern applications of protein conjugates. The targeting of the protein N-terminal alpha-amine group appears a convenient solution to the issue, emerging as a useful and unique reactive site universally present in each protein molecule. Herein, we provide an updated overview of the methodologies developed until today to afford the selective modification of proteins through the targeting of the N-terminal alpha-amine. Chemical and enzymatic strategies enabling the selective labeling of the protein N-terminal alpha-amine group are described. 相似文献
987.
Tomasz Ligor Joanna Zawadzka Grzegorz Strczyski Rosa M. Gonzlez Paredes Anna Wenda-Piesik Ileana Andreea Ratiu Marek Muszytowski 《Molecules (Basel, Switzerland)》2021,26(7)
Volatile organic compounds (VOCs) exiting in urine are potential biomarkers of chronic kidney diseases. Headspace solid phase microextraction (HS-SPME) was applied for extraction VOCs over the urine samples. Volatile metabolites were separated and identified by means of two-dimensional gas chromatography and time of flight mass spectrometry (GC × GC TOF MS). Patients with glomerular diseases (n = 27) and healthy controls (n = 20) were recruited in the study. Different VOCs profiles were obtained from patients and control. Developed methodology offers the opportunity to examine the metabolic profile associated with glomerulopathy. Four compounds found in elevated amounts in the patients group, i.e., methyl hexadecanoate; 9-hexadecen-1-ol; 6,10-dimethyl-5,9-undecadien-2-one and 2-pentanone were proposed as markers of glomerular diseases. 相似文献
988.
Conventional methods generally used to synthesize heterogeneous photocatalysts have some drawbacks, mainly the difficult control/preservation of catalysts’ morphology, size or structure, which strongly affect the photocatalytic activity. Supercritical carbon dioxide (scCO2)-assisted techniques have recently been shown to be a promising approach to overcome these limitations, which are still a challenge. In addition, compared to traditional methods, these innovative techniques permit the synthesis of high-performance photocatalysts by reducing the use of toxic and polluting solvents and, consequently, the environmental impact of long-term catalyst preparation. Specifically, the versatility of scCO2 allows to prepare catalysts with different structures (e.g., nanoparticles or metal-loaded supports) by several supercritical processes for the photocatalytic degradation of various compounds. This is the first updated review on the use of scCO2-assisted techniques for photocatalytic applications. We hope this review provides useful information on different approaches and future perspectives. 相似文献
989.
Noelia Cambeiro-Prez Xiana Gonzlez-Gmez Carmen Gonzlez-Barreiro María Rosa Prez-Gregorio Iva Fernandes Nuno Mateus Victor de Freitas Borja Snchez Elena Martínez-Carballo 《Molecules (Basel, Switzerland)》2021,26(4)
Dihydrochalcones, phlorizin (PZ) and its aglycone phloretin (PT), have evidenced immunomodulatory effects through several mechanisms. However, the differential metabolic signatures that lead to these properties are largely unknown. Since macrophages play an important role in the immune response, our study aimed to characterise human THP-1 macrophages under PZ and PT exposure. A multiplatform-based untargeted metabolomics approach was used to reveal metabolites associated with the anti-inflammatory mechanisms triggered by the dihydrochalcones in LPS-stimulated macrophages, for the first time. Results showed differential phenotypic response in macrophages for all treatments. Dihydrochalcone treatment in LPS-stimulated macrophages mimics the response under normal conditions, suggesting inhibition of LPS response. Antagonistic effects of dihydrochalcones against LPS was mainly observed in glycerophospholipid and sphingolipid metabolism besides promoting amino acid biosynthesis. Moreover, PT showed greater metabolic activity than PZ. Overall, the findings of this study yielded knowledge about the mechanisms of action PZ and PT at metabolic level in modulating inflammatory response in human cells. 相似文献
990.
María Constanza Luciardi María Amparo Blzquez María Rosa Alberto Elena Cartagena Mario Eduardo Arena 《Molecules (Basel, Switzerland)》2021,26(10)
The chemical composition of three Citrus limon oils: lemon essential oil (LEO), lemon terpenes (LT) and lemon essence (LE), and their influence in the virulence factors production and motility (swarming and swimming) of two Pseudomonas aeruginosa strains (ATCC 27853 and a multidrug-resistant HT5) were investigated. The main compound, limonene, was also tested in biological assays. Eighty-four compounds, accounting for a relative peak area of 99.23%, 98.58% and 99.64%, were identified by GC/MS. Limonene (59–60%), γ-terpinene (10–11%) and β-pinene (7–15%) were the main compounds. All lemon oils inhibited specific biofilm production and bacterial metabolic activities into biofilm in a dose-dependent manner (20–65%, in the range of 0.1–4 mg mL−1) of both strains. Besides, all samples inhibited about 50% of the elastase activity at 0.1 mg mL−1. Pyocyanin biosynthesis decreases until 64% (0.1–4 mg mL−1) for both strains. Swarming motility of P. aeruginosa ATCC 27853 was completely inhibited by 2 mg mL−1 of lemon oils. Furthermore, a decrease (29–55%, 0.1–4 mg mL−1) in the synthesis of Quorum sensing (QS) signals was observed. The oils showed higher biological activities than limonene. Hence, their ability to control the biofilm of P. aeruginosa and reduce the production of virulence factors regulated by QS makes lemon oils good candidates to be applied as preservatives in the food processing industry. 相似文献