Search results for "010402 general chemistry"
showing 10 items of 6896 documents
Modulation of Efficient Diiodo-BODIPY in vitro Phototoxicity to Cancer Cells by Carbon Nano-Onions
2020
Photodynamic therapy (PDT) is currently one of the most promising approaches for targeted cancer treatment. It is based on responses of vital physiological signals, namely reactive oxygen species (ROS), which are associated with diseased condition development, such as tumors. This study presents the synthesis, incorporation, and application of a diiodo-BODIPY based photosensitizer, based on a non-covalent functionalization of carbon nano-onions (CNOs). In vitro assays demonstrate that HeLa cells internalize the diiodo-BODIPY molecules, and their CNOs nanohybrids. Upon cell internalization and light exposure, the pyrene-diiodo-BODIPY molecules induce an increase of the ROS level of HeLa cell…
Synthesis, characterization, and cellular investigations of porphyrin– and chlorin–indomethacin conjugates for photodynamic therapy of cancer
2021
Indomethacin is a potent non-steroidal anti-inflammatory drug (NSAID) with a strong selective inhibitor activity towards cyclooxygenase-2 (COX-2), an enzyme that is highly overexpressed in various tumour cells, being involved in tumourigenesis. Concomitantly, porphyrins have gained much attention as promising photosensitizers (PSs) for the non-invasive photodynamic therapy (PDT) of cancer. Herein, we report the design, and determine the singlet oxygen generation capacity and in vitro cellular toxicity of porphyrin- and chlorin-indomethacin conjugates (P2-Ind and C2-Ind). Both the conjugates were obtained in high yields and were characterized by 1H, 19F and 13C NMR as well as by high resolut…
Structural and electronic elucidation of a N-heterocyclic silylene vanadocene adduct
2017
The solid and solution state structure of the vanadium(II) N‐ heterocyclic silylene (NHSi) complex, [(SiIPr)V(Cp)2] (1) is reported ( SiIPr: 1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐diaza‐2‐silacyclopent‐4‐ en‐2‐ylidene). The electronic structure of 1 is probed using combination of magnetic measurements, EPR spectroscopy and computational studies. The V–Si bond strength and complex forming mechanism between vanadocene and NHSi ligand is elucidated using computational methods. peerReviewed
Targeted Drug Delivery in Plants: Enzyme‐Responsive Lignin Nanocarriers for the Curative Treatment of the Worldwide Grapevine Trunk Disease Esca
2019
Abstract Nanocarrier (NC)‐mediated drug delivery is widely researched in medicine but to date has not been used in agriculture. The first curative NC‐based treatment of the worldwide occurring grapevine trunk disease Esca, with more than 2 billion infected plants causing a loss yearly of $1.5 billion, is presented. To date, only repetitive spraying of fungicides is used to reduce chances of infection. This long‐term treatment against Esca uses minimal amounts of fungicide encapsulated in biobased and biodegradable lignin NCs. A single trunk injection of <10 mg fungicide results in curing of an infected plant. Only upon Esca infection, ligninolytic enzymes, secreted by the Esca‐associated fu…
Biocompatibility and Antibacterial Properties of ZnO-Incorporated Anodic Oxide Coatings on TiZrNb Alloy
2020
In a present paper, we demonstrate novel approach to form ceramic coatings with incorporated ZnO nanoparticles (NPs) on low modulus TiZrNb alloy with enhanced biocompatibility and antibacterial parameters. Plasma Electrolytic Oxidation (PEO) was used to integrate ZnO nanoparticles (average size 12&ndash
Toward Sustainable PLA-Based Multilayer Complexes with Improved Barrier Properties
2019
Poly(lactic acid) or PLA is currently considered as one of the most promising substitutes of conventional plastics, with low environmental impact, especially for food packaging applications. Nevertheless, some drawbacks, such as high permeability to oxygen, are still limiting its industrial applications. The objective of this study was to highly increase the oxygen barrier performance of PLA without compromising its sustainable nature and following the principles of circular economy perspective. Coproducts coming from mill industries, such as wheat gluten proteins (WG), were used to produce PLA-WG-PLA multilayer complexes with improved barrier performance. Different technologies of industri…
Self-Consistent Charge Density-Functional Tight-Binding Parametrization for Pt–Ru Alloys
2017
We present a self-consistent charge density-functional tight-binding (SCC-DFTB) parametrization for PtRu alloys, which is developed by employing a training set of alloy cluster energies and forces obtained from Kohn-Sham density-functional theory (DFT) calculations. Extensive simulations of a testing set of PtRu alloy nanoclusters show that this SCC-DFTB scheme is capable of capturing cluster formation energies with high accuracy relative to DFT calculations. The new SCC-DFTB parametrization is employed within a genetic algorithm to search for global minima of PtRu clusters in the range of 13-81 atoms and the emergence of Ru-core/Pt-shell structures at intermediate alloy compositions, consi…
Self-healing, luminescent metallogelation driven by synergistic metallophilic and fluorine–fluorine interactions
2020
Square planar platinum(ii) complexes are attractive building blocks for multifunctional soft materials due to their unique optoelectronic properties. However, for soft materials derived from synthetically simple discrete metal complexes, achieving a combination of optical properties, thermoresponsiveness and excellent mechanical properties is a major challenge. Here, we report the rapid self-recovery of luminescent metallogels derived from platinum(ii) complexes of perfluoroalkyl and alkyl derivatives of terpyridine ligands. Using single crystal X-ray diffraction studies, we show that the presence of synergistic platinum-platinum (PtMIDLINE HORIZONTAL ELLIPSISPt) metallopolymerization and f…
PtII versus PdII-assisted [2+3] cycloadditions of nitriles and nitrone. Synthesis of nitrile-derived arylamido platinum(II) and Δ4-1,2,4-oxadiazoline…
2019
Abstract The reactions of bis(organonitrile) platinum(II) complexes trans-[PtCl2(N CR)2] (R = C6H4(p-HC O), CH2C6H4(p-CH3)) with pyrroline N-oxide −O+N CHCH2CH2CMe2 afford arylamido platinum(II) complexes trans-[PtCl2{(O CR)N CCH2CH2CMe2NH}2] (R = C6H4(p-HC O) (1), CH2C6H4(p-CH3) (2)). The spectral data of 1 and 2 show that the oxadiazoline rings in both cases have opened by a spontaneous N O bond cleavage to form (Z)-p-formyl-N-(5,5-dimethylpyrrolidin-2-ylidene)benzamide or (Z)-N-(5,5-dimethylpyrrolidin-2-ylidene)-2-p-tolylacetamide ligands, respectively, where the N-atoms of the benzamide or acetamide moieties coordinate to platinum(II) metal centre in trans positions. However, the reacti…
Non-conventional synthesis and photophysical studies of platinum(ii) complexes with methylene bridged 2,2′-dipyridylamine derivatives
2019
Methylene bridged 2,2′-dipyridylamine (dpa) derivatives and their metal complexes possess outstanding properties due to their inherent structural flexibility. Synthesis of such complexes typically involves derivatization of dpa followed by coordination on metals, and may not always be very efficient. In this work, an alternative synthetic approach, involving the derivatization step after – rather than prior to – coordination of dpa on metal center, is proposed and applied to synthesis of a number of platinum(II) complexes with substituted benzyldi(2-pyridyl)amines. Comparison with the more conventional synthetic route reveals greater efficiency and versatility of the proposed approach. The …