0000000000014365

AUTHOR

Sameh El Sayed

0000-0003-1564-2615

showing 9 related works from this author

A Chromogenic Probe for the Selective Recognition of Sarin and Soman Mimic DFP

2014

The synthesis, characterization and sensing features of a novel probe 1 for the selective chromogenic recognition of diisopropylfluorophosphate (DFP), a sarin and soman mimic, in 99:1 (v/ v) water/acetonitrile and in the gas phase is reported. Colour modulation is based on the combined reaction of phosphorylation of 1 and fluoride-induced hydrolysis of a silyl ether moiety. As fluoride is a specific reaction product of the reaction between DFP and the OH group, the probe shows a selective colour modulation in the presence of this chemical. Other nerve agent simulants, certain anions, oxidant species and other organophosphorous compounds were unable to induce colour changes in 1. This is one…

SarinAqueous solutionsomanChemistryChromogenicQUIMICA INORGANICAContext (language use)General Chemistrynerve agentsCommunicationsToxicologysarinchemistry.chemical_compoundQUIMICA ORGANICASomanmedicineMoietydiisopropylfluorophosphatechromogenic probeNerve agentmedicine.drugNuclear chemistryTabun
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2,4,5-Triaryl imidazole probes for the selective chromo-fluorogenic detection of Cu(II). Prospective use of the Cu(II) complexes for the optical reco…

2019

The sensing behaviour toward metal cations and biothiols of two 2,4,5-triarylimidazole probes (3a and 3b) is tested in acetonitrile and in acetonitrile-water. In acetonitrile the two probes present charge-transfer absorption bands in the 320-350 nm interval. Among all cations tested only Cu(11) is able to induce bathochromic shifts of the absorption band in the two probes, which is reflected in marked colour changes. Colour modulations are ascribed to the formation of 1:1 Cu(II)-probe complexes in which the cation interacts with the imidazole acceptor heterocycle. Besides, the two probes present intense emission bands (at 404 and 437 nm for 3a and 3b respectively) in acetonitrile that are q…

010402 general chemistryPhotochemistryCu(II) detection01 natural sciencesCu(II) imagingInorganic ChemistryMetalchemistry.chemical_compoundBathochromic shiftMaterials ChemistryImidazolePhysical and Theoretical ChemistryAcetonitrileImidazole-based probesAqueous solutionScience & Technology010405 organic chemistryGSH imagingAcceptor0104 chemical sciences3. Good healthchemistryAbsorption bandvisual_artvisual_art.visual_art_mediumHypsochromic shiftBiothiols recognition
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Acetylcholinesterase-Capped Mesoporous Silica Nanoparticles That Open in the Presence of Diisopropylfluorophosphate (a Sarin or Soman Simulant)

2016

Mesoporous silica nanoparticles loaded with rhodamine B and capped with acetylcholinesterase are able to be selectively opened and deliver their cargo in the presence of nerve agent simulant diisopropyl fluorophosphate (DFP).

NANOCAPSULESRESPONSIVE CONTROLLED-RELEASESarinGATED MATERIALSNanoparticle02 engineering and technologyCHEMICAL WARFARE AGENTS010402 general chemistry01 natural sciencesBiochemistryNanocapsuleschemistry.chemical_compoundQUIMICA ORGANICADESIGNSomanmedicineRhodamine BOrganic chemistryDRUG-DELIVERYPhysical and Theoretical ChemistryNerve agentNANOCONTAINERSChemistryQUIMICA INORGANICAOrganic ChemistryDNAMesoporous silica021001 nanoscience & nanotechnologyGUEST MOLECULES0104 chemical sciencesDiisopropyl fluorophosphateDCNP0210 nano-technologymedicine.drugNuclear chemistryOrganic Letters
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Highly selective fluorescence detection of hydrogen sulfide by using an anthracene-functionalized cyclam-CuII complex

2013

An anthracene-functionalised cyclam-copper(II) complex for the detection of HS- in aqueous environments has been prepared. This probe displays poor fluorescence but can selectively and sensitively detect HS- anions in water over other anions, biothiols and common oxidants such as H2O2 through remarkably enhanced emission. This turn-on response in the presence of the HS- anion is ascribed to a demetallation reaction that inhibits emission quenching observed in the initial complex as a result of the presence of the paramagnetic Cu2+ centre. Moreover, real-time fluorescence imaging measurements confirm that probe [Cu(1)](2+) can be easily used to detect intracellular HS- at micromolar concentr…

AnthraceneFluorescence-lifetime imaging microscopyAqueous solutionSensorsHydrogen sulfideInorganic chemistryQUIMICA INORGANICAchemistry.chemical_elementPhotochemistryCopperFluorescenceIonInorganic Chemistrychemistry.chemical_compoundQUIMICA ORGANICAchemistryCyclamQUIMICA ANALITICAFluorescent probesSulfurCopper
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A new fluorescent "turn-on" chemodosimeter for the detection of hydrogen sulfide in water and living cells

2013

[EN] A new fluorescent turn-on probe for the selective detection of hydrogen sulfide in water and living cells based on a 8-hydroxyquinoline fluorophore functionalized with a 2,6-dinitrophenyl ether moiety has been developed.

FluorophoreReagentsChemosensorsH2SGeneral Chemical EngineeringHydrogen sulfideQUIMICA INORGANICAAnionThiolysisEtherGeneral ChemistryPhotochemistryProbeFluorescenceTurn (biochemistry)chemistry.chemical_compoundQUIMICA ORGANICAThiolysischemistryReagentMoiety
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A Chemosensor Bearing Sulfonyl Azide Moieties for Selective Chromo-Fluorogenic Hydrogen Sulfide Recognition in Aqueous Media and in Living Cells

2014

A simple chemodosimeter based on a sulfonyl azide dye (1-Az), which displayed a highly selective response toward hydrogen sulfide anion in mixed aqueous media, was synthesised and characterised. Addition of hydrogen sulfide to acetonitrile/HEPES 1:1 solutions of 1-Az induced a clear colour change from red-orange to yellow, which was easily detected by the naked eye, and by an enhancement in the emission intensity. Other common anions, thiol-containing biomolecules and oxidants did not induce any noticeable colour or fluorescence modulation in the probe. The chemodosimeter also showed a good sensitivity, with limits of detection of 11.91 and 0.63 μM by using UV/Vis or fluorescence measuremen…

HEPESSulfonylchemistry.chemical_classificationHydrogen sulfideOrganic Chemistrychemistry.chemical_elementPhotochemistryFluorescenceSulfurchemistry.chemical_compoundchemistryAzideNaked eyePhysical and Theoretical ChemistryAcetonitrileEuropean Journal of Organic Chemistry
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Selective chromo-fluorogenic detection of trivalent cations in aqueous environments using a dehydration reaction

2016

[EN] Trivalent cations (Al3+, Fe3+, Cr3+, As3+, In3+ and Ga3+) induced a dehydration reaction of a chemodosimeter in water that is coupled with colour and emission changes.

Aqueous solution010405 organic chemistryChemistryQUIMICA INORGANICAInorganic chemistryGeneral Chemistry010402 general chemistryPhotochemistry01 natural sciencesCatalysis0104 chemical sciencesQUIMICA ORGANICADehydration reactionMaterials ChemistryQualitative inorganic analysisNew Journal of Chemistry
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Chromogenic Detection of Aqueous Formaldehyde Using Functionalized Silica Nanoparticles

2016

Silica nanoparticles functionalized with thiol reactive units and bulky polar polyamines were used for the selective colorimetric detection of formaldehyde. The reaction of thiols groups in the nanoparticles surface with a squaraine dye resulted in loss of the pi-conjugation of the chromophores, and the subsequent bleaching of the solution. However, when formaldehyde was present in the suspension, the thiol-squaraine reaction was inhibited and a chromogenic response was observed. A selective response to formaldehyde was observed only when the thiol and polyamine groups were anchored to the silica surface. The observed selective response was ascribed to the fact that bulky polyamines generat…

aqueous detectionFormaldehydeNanoparticle02 engineering and technologysilica nanoparticles010402 general chemistryPhotochemistry01 natural scienceschemistry.chemical_compoundQUIMICA ORGANICAhybrid materialsGeneral Materials SciencesensingDetection limitchemistry.chemical_classificationSquaraine dyeAqueous solutionChromogenicQUIMICA INORGANICA021001 nanoscience & nanotechnology0104 chemical scienceschemistryThiolformaldehyde0210 nano-technologyHybrid material
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Azide and sulfonylazide functionalized fluorophores for the selective and sensitive detection of hydrogen sulfide

2015

[EN] Three fluorescent probes (1–3) for the selective and sensitive detection of hydrogen sulfide have been synthesized and characterized. Probe 1 is a coumarin derivative functionalized with an azide moiety whereas 2 contain the azide reactive group into a naphthalene fluorophore backbone. Probe 3 is composed also by a naphthalene fluorophore but, in this case, functionalized with a sulfonylazide reactive moiety. Probes 1 and 3 are non-fluorescent whereas 2 is weakly emissive in HEPES (10 mM, pH 7.4)–DMSO 99:1 (v/v). The emission behavior of the three probes was tested against selected anions, bio-thiols and oxidant molecules. Of all the chemical species tested, only HS− is able to induce …

FluorophoreHydrogen sulfidePhotochemistryFluorescencechemistry.chemical_compoundQUIMICA ORGANICAQUIMICA ANALITICAMaterials ChemistryMoleculeMoietyElectrical and Electronic EngineeringInstrumentationDetection limitHEPESHydrogen sulfideQUIMICA INORGANICAMetals and AlloysCondensed Matter PhysicsFluorescenceSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsAzidechemistryIn vivo detectionSulfonylazideAzideSensors and Actuators B: Chemical
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