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1.
J Fluoresc ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38530563

ABSTRACT

In this investigation, we explore the integration of lanthanides into Metal-Organic Frameworks (MOFs) to enable Near-Infrared (NIR) emission. Specifically, we focus on Lanthanide-Naphthalene Dicarboxylate based MOFs (Ln-MOFs), incorporating elements such as Praseodymium (Pr), Samarium (Sm), Dysprosium (Dy), and Erbium (Er). The synthesis of Ln-MOFs is achieved via the hydrothermal method. The structure, morphology, thermal stability, and luminescence properties of synthesized Ln-MOFs have been evaluated through different characterization techniques. Upon photoexcitation at 350 nm, Ln-MOFs show the emission in the Visible and NIR region. Further, the luminescence intensity of Ln-MOFs enhanced by 2-3 folds in the visible region and 6-8 folds in NIR region after exposing to Gamma irradiation at 150 kGy. Cytotoxic effect on the viability of MDA-MB 231 and MDA-MB 468 Triple negative breast cancer (TNBC) cells was evaluated by MTT assay. The results revealed that among all synthesized MOFs, Pr-MOF exhibited an aggressive cytotoxic effect. Additionally, analysis of phase-contrast microscopy data indicates that Pr-MOF induces alterations in the morphology of both MDA-MB 231 and MDA-MB 468 TNBC cells when compared to untreated controls. The findings in this study reveal the utilization of Ln-MOFs for studying cytotoxicity and highlight their ability to enhance near-infrared (NIR) emission when exposed to gamma radiation.

2.
Antioxidants (Basel) ; 11(4)2022 Mar 31.
Article in English | MEDLINE | ID: mdl-35453373

ABSTRACT

The present report presents a green method for the rapid biogenic synthesis of nanoparticles that offers several advantages over the current chemical and physical procedures. It is easy and fast, eco-friendly, and does not involve any precious elements, hazardous chemicals, or harmful solvents. The synthesized ZnO nanoparticles were characterized using different techniques, such as UV-Visible spectroscopy. The surface plasmon resonance confirmed the formation of ZnO nanoparticles at 344 nm, using UV-Visible spectroscopy. The leaf extract acts as a source of phytochemicals and is primarily used for the reduction and then the formation of stable ZnO nanoparticles by the characteristic functional groups of the extract; the synthesized ZnO nanoparticles were identified using FTIR spectroscopy. The crystalline nature of ZnO-NPs was confirmed via powder X-ray diffraction (XRD). Size and morphology were measured via high resolution transmission electron microscopy (HR-TEM) analysis. The stability of the nanoparticles is established using dynamic light scattering (DLS) and thermogravimetric analysis (TGA). The synthesized ZnO nanoparticles have been found to be a good and efficient catalyst for the synthesis of novel 1,2-dihydro quinazoline derivatives under the green method via a one-pot reaction of 2-amino benzophenone, 1,3-diphenyl-1H-pyrazole carbaldehydes, and ammonium acetate. The synthesized compounds (4a-o) were characterized by the 1H NMR, 13C NMR, and HRMS spectra and were further validated for free-radical scavenging activity. The synthesized ZnO nanoparticles exhibited good antioxidant activity.

3.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 3): m69-70, 2015 Mar 01.
Article in English | MEDLINE | ID: mdl-25844213

ABSTRACT

In the title compound, [FeIr(C5H5)(C20H14N3)Cl3]·2CH3CN, the central Ir(III) atom is sixfold coordinated by three chloride ligands and three terpyridine N atoms in a slightly distorted octa-hedral fashion. The terpyridine ligand is functionalized at the 4'-position with a ferrocenyl group, the latter being in an eclipsed conformation. In the crystal, mol-ecules are stacked in rows parallel to [001], with the aceto-nitrile solvent mol-ecules situated between the rows. An extensive network of intra- and inter-molecular C-H⋯Cl inter-actions is present, stabilizing the three-dimensional structure.

4.
J Mater Chem B ; 2(37): 6406-6411, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-32262157

ABSTRACT

The commercial polymeric anhydride poly(methyl vinyl ether-alt-maleic anhydride) (PVM/MA) is converted by reaction with NaOH to give poly(methyl vinyl ether-alt-mono-sodium maleate) (PVM/Na-MA). By addition of AgNO3-solution, the formation of the silver(i) supramolecular polymer hydrogel poly[methyl vinyl ether-alt-mono-sodium maleate]·AgNO3 is reported. Freeze-dried samples of the hydrogel show a mesoporous network of polycarboxylate ligands that are crosslinked by silver(i) cations. In the intact hydrogel, ion-exchange studies are reported and it is shown that Ag+ ions can be exchanged by copper(ii) cations without disintegration of the hydrogel. The silver(i) hydrogel shows effective antibacterial activity and potential application as burn wound dressing.

5.
ChemSusChem ; 6(8): 1366-75, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23843354

ABSTRACT

A series of Os(II) sensitizers (TFOS-x, in which x=1, 2, or 3) with a single 4,4'-dicarboxy-2,2'-dipyridine (H2 dcbpy) anchor and two chelating 2-pyridyl (or 2-pyrimidyl) triazolate ancillaries was successfully prepared. Single-crystal X-ray structural analysis showed that the core geometry of the Os(II) -based sensitizers consisted of one H2 dcbpy unit and two eclipsed cis-triazolate fragments; this was notably different from the Ru(II) -based counterparts, in which the azolate (both pyrazolate and triazolate) fragments are located at the mutual trans-positions. The basic properties were extensively probed by using spectroscopic and electrochemical methods as well as time-dependent density functional theory (TD-DFT) calculations. Fabrication of dye-sensitized solar cells (DSCs) was then attempted by using the I(-) /I3 (-) -based electrolyte solution. One such DSC device, which utilized TFOS-2 as the sensitizer, showed promising performance characteristics with a short-circuit current density (JSC ) of 15.7 mA cm(-2) , an open-circuit voltage of 610 mV, a fill factor of 0.63, and a power conversion efficiency of 6.08 % under AM 1.5G simulated one-sun irradiation. Importantly, adequate incident photon-to-current conversion efficiency performances were observed for all TFOS derivatives over the wide spectral region of 450 to 950 nm, showing a panchromatic light harvesting capability that extended into the near-infrared regime. Our results underlined a feasible strategy for maximizing JSC and increasing the efficiency of DSCs.


Subject(s)
Coloring Agents/chemistry , Drug Design , Electric Power Supplies , Heterocyclic Compounds/chemistry , Organometallic Compounds/chemistry , Osmium/chemistry , Solar Energy , Electrochemistry , Models, Molecular , Molecular Conformation , Organometallic Compounds/chemical synthesis , Ruthenium/chemistry
6.
Chemistry ; 18(50): 16061-72, 2012 Dec 07.
Article in English | MEDLINE | ID: mdl-23111823

ABSTRACT

Three novel electron donor-acceptor conjugated polymers (P1-P3) bearing various imidazole pendants have been synthesized. Their excellent photophysical and electrochemical properties make them suitable transduction materials for chemosensing applications. Indeed, polymers P1-P3 have been found to show remarkable sensing capabilities towards H(+) and Fe(2+) in semi-aqueous solutions. Upon titration with H(+), polymers P1 and P2 showed hypsochromic shifts of their absorptions and photoluminescence (PL) maxima with enhanced fluorescence intensities. However, P3 showed diminished absorption and fluorescence intensities under similar conditions due to static quenching. The anomalous behavior of P3 compared with P1 and P2 has been clarified in terms of electronic distributions through computational analysis. Furthermore, P3 (K(SV) = 1.03×10(7)) showed a superior sensing ability towards Fe(2+) compared with P1 (K(SV) = 2.01×10(6)) and P2 (K(SV) = 4.12×10(6)) due to its improved molecular wire effect. Correspondingly, the fluorescence lifetime of P3 was greatly decreased (almost 11-fold) compared to those of polymers P1 (4.6-fold) and P2 (6.2-fold) in the presence of Fe(2+). By means of a fluorescence on-off-on approach, chemosensing reversibilities in protonation-deprotonation and metallation-demetallation have been achieved by employing triethylamine (TEA) and the disodium salt of ethylenediaminetetraacetic acid (Na(2)-EDTA)/phenanthroline, respectively, as suitable counter ligands. (1)H NMR titrations have revealed the unique behavior of P3 compared with P1 and P2. To the best of our knowledge, there have been no previous reports of Fe(2+) sensors based on single imidazole receptors conjugated to a main-chain polymer showing such a diverse sensitivity pattern depending on their attached substituents.


Subject(s)
Fluorescent Dyes/chemistry , Imidazoles/chemistry , Iron/chemistry , Polymers/chemistry , Polymers/chemical synthesis , Ligands , Magnetic Resonance Spectroscopy , Molecular Structure
7.
Macromol Rapid Commun ; 33(6-7): 528-33, 2012 Apr 13.
Article in English | MEDLINE | ID: mdl-22228602

ABSTRACT

Two random (Zn(II)-based P1-P2) and two alternating (Ru(II)-based P3-P4) metallo-copolymers containing bis-terpyridyl ligands with various central donor (i.e., fluorene or carbazole) and acceptor (i.e., benzothiadiazole) moieties were synthesized. The effects of electron donor-acceptor interactions with metal (Zn(II) and Ru(II)) ions on their thermal, optical, and electrochemical properties were investigated. Because of the strong ICT transitions between donor and acceptor ligands in both Zn(II)- and Ru(II)-based metallo-coplymers and MLCT transitions in Ru(II)-based metallo-coplymers, the absorption spectra covered a broad range of 260-750 nm with the band gaps of 1.57-1.77 eV. In addition, the introduction of Ru(II)-based metallo-coplymer P4 mixed with PC(60)BM as an active layer of the BHJ solar cell device exhibited the highest PCE value up to 0.90%.


Subject(s)
Photochemistry/instrumentation , Polymers/chemical synthesis , Pyridines/chemistry , Ruthenium/chemistry , Chemistry Techniques, Synthetic , Molecular Structure , Polymers/chemistry
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