Search results for "PORP"

showing 10 items of 567 documents

Supramolecular Assemblies Based on Complexes of Nonionic Amphiphilic Cyclodextrins and a meso-Tetra(4- sulfonatophenyl)porphine Tributyltin(IV) Deriv…

2013

Amphiphilic cyclodextrin (ACyD) provides water-soluble and adaptable nanovectors by modulating the balance between the hydrophobic and hydrophilic chains at both CyD sides. This work aimed to design nanoassemblies based on nonionic and hydrophilic ACyD (SC6OH) for the delivery of a poor-water-soluble organotin(IV)-porphyrin derivative [(Bu3Sn)4TPPS] to melanoma cancer cells. To characterize the porphyrin derivatives under simulated physiological conditions, a speciation was performed using complementary techniques. In aqueous solution (≤ 20 μM), (Bu3Sn)4TPPS primarily exists as a monomer (2 in Figure 1), as suggested by the low static anisotropy (ρ ≈ 0.02) with a negligible formation of por…

Polymers and PlasticsCell SurvivalSurface PropertiesPotentiometric titrationSupramolecular chemistryAntineoplastic AgentsBioengineeringBiomaterialsStructure-Activity RelationshipSurface-Active Agentschemistry.chemical_compoundDrug Delivery SystemsAmphiphilePolymer chemistryTumor Cells CulturedMaterials ChemistryHumansOrganic chemistryParticle SizeMelanomaMELANOMA porphyrins organotin(IV)Cell Proliferationchemistry.chemical_classificationCyclodextrinsAqueous solutionCell DeathDose-Response Relationship DrugMolecular StructureCyclodextrinPorphyrinNanomedicineMonomerchemistrySettore CHIM/03 - Chimica Generale E InorganicaDrug Screening Assays AntitumorTrialkyltin CompoundsDrug carrier
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Variability of the fimA gene in Porphyromonas gingivalis isolated from periodontitis and non-periodontitis patients

2011

Objective: The goal of this study was to determine the genetic variability of the fimA gene in Porphyromonas gingivalis isolates from Spanish patients. Study Design: Pooled subgingival samples were taken, processed and cultured in non-selective blood agar medium. Pure cultures of one to six isolates per patient were obtained and PCR and PCR-RFLP were used for fimbrillin gene (fimA) type determination of the extracted genomic (DNA). Results: Two hundred and twenty four Porphyromonas gingivalis isolates from 65 patients were analyzed consisting of 15 non-periodontitis patients (66 isolates) and 50 with periodontitis (158 isolates). Genotype II was the most prevalent (50.9%), while the other t…

PopulationFimbriaOdontologíaBiologyMicrobiologyFimbriae ProteinsAgar plateGenotypemedicineBacteroidaceae InfectionsHumansPeriodontologyGenetic variabilityeducationPeriodontitisGeneral DentistryPorphyromonas gingivalisPeriodontitiseducation.field_of_studybiochemical phenomena metabolism and nutritionmedicine.diseasebiology.organism_classification:CIENCIAS MÉDICAS [UNESCO]Ciencias de la saludOtorhinolaryngologyUNESCO::CIENCIAS MÉDICASSurgeryResearch-ArticleFimbriae ProteinsPorphyromonas gingivalis
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PI-Extension of porphyrins via intramolecular aromatic oxidative C-N coupling

2019

Π-extension of porphyrins has been performed via intramolecular oxidative C-N coupling of peripheral pyridinyl fragment(s) with the porphyrin core. These fusion reactions lead to the formation of C-N bond(s) between the substituent(s) and the porphyrin. The precursors were functionnalized with 2-mercaptopyridine, 8-hydoxyquinoline and 2-picoline at their meso or β-pyrrolic positions via aromatic nucleophlic substitution, cross-coupling reaction or reaction of the macrocycle with organolithium reagents. Voltametric analyses revealed some marked differences on the reactivity of the porphyrins depending on their substitution pattern and metalation (nickel(II) or zinc(II)). Chemical and electro…

PorphyrinHeterocyclic chemistryChimie hétérocycliqueÉlectrochimie moléculairePorphyrineSynthèse mhétérocycliqueulti-Étapes[CHIM.CRIS]Chemical Sciences/Cristallography[CHIM.CRIS] Chemical Sciences/CristallographyFusionMulti-Step synthesisMolecular electrochemistry
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Design of new porphyrin/Fe-loaded TiO2 composites for the efficient degradation of 4-nitrophenol by heterogeneous photo Fenton process

2012

Porphyrin/Fe loaded TiO2 PhotoFenton
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Porphyrin amino acids-amide coupling, redox and photophysical properties of bis(porphyrin) amides.

2013

New trans-AB2C meso-substituted porphyrin amino acid esters with meso-substituents of tunable electron withdrawing power (B = mesityl, 4-C6H4F, 4-C6H4CF3, C6F5) were prepared as free amines 3a-3d, as N-acetylated derivatives Ac-3a-Ac-3d and corresponding zinc(II) complexes Zn-Ac-3a-Zn-Ac-3d. Several amide-linked bis(porphyrins) with a tunable electron density at each porphyrin site were obtained from the amino porphyrin precursors by condensation reactions (4a-4d) and mono- and bis(zinc(II)) complexes Zn(2)-4d and Zn(1)Zn(2)-4d were prepared. The electronic interaction between individual porphyrin units in bis(porphyrins) 4 is probed by electrochemical experiments (CV, EPR), electronic abso…

PorphyrinsAbsorption spectroscopyMetalationchemistry.chemical_elementZincPhotochemistryRedoxlaw.inventionInorganic Chemistrychemistry.chemical_compoundlawAmidePolymer chemistryOrganometallic CompoundsAmino AcidsElectron paramagnetic resonanceMolecular StructureElectron Spin Resonance SpectroscopyCondensation reactionPhotochemical ProcessesPorphyrinAmidesZincchemistryQuantum TheoryOxidation-ReductionDalton transactions (Cambridge, England : 2003)
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Acceleration of the through space S1 energy transfer rates in cofacial bisporphyrin bio-inspired models by virtue of substituents effect on the Först…

2011

The singlet k(ET) for cofacial β-octaalkylporphyrin/bis(meso-aryl)porphyrin dyads increases linearly with the gap between the donor-acceptor 0-0 fluorescence peaks at 77 K.

PorphyrinsEnergy transferLight-Harvesting Protein ComplexesMetals and AlloysAntenna effectGeneral ChemistrySpace (mathematics)PorphyrinFluorescenceCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialschemistry.chemical_compoundAccelerationSpectrometry FluorescenceBacterial ProteinsEnergy TransferModels ChemicalchemistryChemical physicsMaterials ChemistryCeramics and CompositesSinglet stateAtomic physicsPhotosystemChemical Communications
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Application of 3-Quinolinoyl Picket Porphyrins to the Electroreduction of Dioxygen to Water: Mimicking the Active Site of Cytochromec Oxidase

2001

International audience

PorphyrinsHemeproteinReducing agentIronchemistry.chemical_elementPhotochemistryElectrochemistry[ CHIM ] Chemical SciencesBiochemistryOxygenElectron Transport Complex IVO-O activationcytochrome c oxidase[CHIM]Chemical SciencesCytochrome c oxidaseBinding siteMolecular BiologyComputingMilieux_MISCELLANEOUSBinding SitesbiologyChemistryMolecular MimicryOrganic ChemistryActive siteElectron Transport Complex IVheme proteinsoxidoreductasesOxygenelectrochemistryReducing Agentsbiology.proteinMolecular MedicineIndicators and ReagentsSpectrophotometry UltravioletOxidation-ReductionCopperChemBioChem
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Selective chemisorption of carbon monoxide by organic-inorganic hybrid materials incorporating cobalt(III) corroles as sensing components.

2007

Twenty-one hybrid materials incorporating cobalt(III) corrole complexes were synthesized by a sol–gel process or by grafting the metallocorrole onto a mesostructured silica of the SBA-15 type. All the materials show an almost infinite selectivity for carbon monoxide with respect to dinitrogen and dioxygen in the low-pressure domain where the chemisorption phenomenon is predominant. This peculiar property is of prime importance for an application as a CO sensor. The selectivity slightly decreases at high pressures where nonselective physisorption phenomena mainly occur. The percentage of active sites for CO chemisorption ranges from 22 to 64 %. This low percentage may be attributable to inte…

PorphyrinsInorganic chemistrychemistry.chemical_element010402 general chemistry01 natural sciencesCatalysischemistry.chemical_compoundAdsorptionPhysisorptionCorroleOrganic ChemicalscorrolesComputingMilieux_MISCELLANEOUSCO detection010405 organic chemistryChemistryLigandsol-gel processesChemistry PhysicalOrganic Chemistry[CHIM.MATE]Chemical Sciences/Material chemistryGeneral ChemistryCobaltSilicon Dioxide0104 chemical sciencesChemistryChemisorption[ CHIM.MATE ] Chemical Sciences/Material chemistryAdsorptionGasesHybrid materialCobaltGelsCarbon monoxideorganic-inorganic hybrid compositesChemistry (Weinheim an der Bergstrasse, Germany)
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Clarification of the oxidation state of cobalt corroles inheterogeneous and homogeneous catalytic reduction of dioxygen

2008

Co(III) corroles were investigated as efficient catalysts for the reduction of dioxygen in the presence of perchloric acid in both heterogeneous and homogeneous systems. The investigated compounds are (5,10,15-tris(pentafluorophenyl)corrole)cobalt (TPFCor)Co, (10-pentafluorophenyl-5,15-dimesitylcorrole)cobalt (F 5PhMes 2Cor)Co, and (5,10,15-trismesitylcorrole)cobalt (Mes 3Cor)Co, all of which contain bulky substituents at the three meso positions of the corrole macrocycle. Cyclic voltammetry and rotating ring-disk electrode voltammetry were used to examine the catalytic activity of the compounds when adsorbed on the surface of a graphite electrode in the presence of 1.0 M perchloric acid, a…

PorphyrinsInorganic chemistrychemistry.chemical_element010402 general chemistry01 natural sciencesRedoxMedicinal chemistryCatalysisInorganic Chemistry[ CHIM.CATA ] Chemical Sciences/Catalysischemistry.chemical_compoundcorroleOxidation stateElectrochemistryOrganometallic CompoundsPerchloric acidPhysical and Theoretical ChemistryCorroleElectrodesComputingMilieux_MISCELLANEOUSPerchlorates010405 organic chemistryElectron Spin Resonance Spectroscopy[CHIM.CATA]Chemical Sciences/Catalysiscobaltcatalytic reduction of dioxygen0104 chemical sciencesOxygenBenzonitrilechemistryRadical ionSpectrophotometry UltravioletCyclic voltammetryOxidation-ReductionCobalt
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Polystyrene Sulfonate–Porphyrin Assemblies: Influence of Polyelectrolyte and Porphyrin Structure

2011

In this study, electrostatic self-assembly of different polystyrene sulfonates and a set of tetravalent cationic porphyrins is investigated. It is shown that association of linear polystyrene sulfonates of different molar masses yields finite size nanoscale assemblies that are stable in aqueous solution. Aggregates are compared to the ones of cylindrical brushes, revealing that both form assemblies in the 100 nm range with the charge ratio (molar ratio of porphyrin charges to polyelectrolyte charges) being determining, while the morphology of the resulting network-like assemblies is different for both polyelectrolyte architectures. For the smallest 8k polystyrene sulfonate, in addition, sto…

PorphyrinsLightStatic ElectricityMicroscopy Atomic ForcePorphyrin structurePolystyrene sulfonatechemistry.chemical_compoundScattering Small AnglePolymer chemistryMaterials ChemistryScattering RadiationPhysical and Theoretical ChemistryCationic polymerizationPorphyrinPolyelectrolyteNanostructuresSurfaces Coatings and FilmsQuaternary Ammonium CompoundsNeutron DiffractionZincchemistryPolystyrenesSpectrophotometry UltravioletSelf-assemblyPolystyreneCopperThe Journal of Physical Chemistry B
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