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Tony D. James - One of the best experts on this subject based on the ideXlab platform.
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fluorescent Alizarin phenylboronic acid ensembles design of self organized molecular sensors for metal ions and anions
Journal of Materials Chemistry, 2005Co-Authors: Yuji Kubo, Tomohisa Ishida, Atushi Kobayashi, Tony D. JamesAbstract:Alizarin–phenylboronic acid interactions were used in a new design strategy for self-organized fluorescent sensors of metal ions and anions. First, Alizarin Red S (ARS), which binds effectively to phenylboronic acid (PBA) at neutral conditions in water, proved to be an excellent fluorescent indicator for the selective detection of metal ions; the fluorescent-active ARS–PBA ensemble causes an efficient and selective quenching in the fluorescence by adding metal ions. It was also found that anion-induced phenylboronates can bind effectively to Alizarin and greatly enhance the fluorescence in MeOH. The observation makes it possible to design new self-organized anion sensory systems composed of Alizarin (as reporter) and phenylboronic acids (PBAs, as receptor), such as PBA or 3-nitrophenylboronic acid (NPBA). By combining spectroscopic studies (UV–vis and fluorescence) and 11B NMR measurements, a ternary complex (F−–Alizarin–PBAs) has been determined. The resulting self-organized sensory system is applicable even to the detection of anions dissolved in water, when liquid [Alizarin, PBA, 18-crown-6 in CH2ClCH2Cl]–liquid [KX (X = halogen, OAc, H2PO4) in water at pH 5.5] two-phase extraction is employed.
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detection of anions using a fluorescent Alizarin phenylboronic acid ensemble
Chemical Communications, 2005Co-Authors: Yuji Kubo, Tomohisa Ishida, Atsushi Kobayashi, Yoshihiro Misawa, Tony D. JamesAbstract:Selective anion-induced organization of phenylboronic acids and Alizarin results in a new TURN-ON fluorescent sensor for anions in MeOH.
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A d-glucose selective fluorescent assay
Tetrahedron Letters, 2002Co-Authors: Susumu Arimori, Christopher J. Ward, Tony D. JamesAbstract:A d-glucose selective competition assay has been devised using Alizarin Red S and diboronic acid 2 in buffered aqueous solution.
Santiago Sanchezcortes - One of the best experts on this subject based on the ideXlab platform.
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extractionless non hydrolysis surface enhanced raman spectroscopic detection of historical mordant dyes on textile fibers
Journal of Raman Spectroscopy, 2010Co-Authors: Z Jurasekova, Jose Vicente Garciaramos, Santiago Sanchezcortes, E Del Puerto, G Bruno, Concepcion DomingoAbstract:Alizarin and carminic acid have been detected in reference wool and linen fibers dyed with madder and cochineal, respectively, through surface-enhanced Raman scattering (SERS) measurements carried out directly on the fiber, without previous hydrolysis of the mordant-dye complex. For such purpose, Ag nanoparticles were produced and immobilized in situ via the laser photoreduction of a silver nitrate aqueous solution in contact with the fiber. Control SERS spectra of pure dyes (Alizarin, purpurin and carminic acid, as well as of mixtures of the first two) on similar Ag nanoparticles were also obtained. The method has been applied to one archeological Coptic textile (6th–8th A.D.) of Egyptian origin, where Alizarin has been clearly identified. Other mordant dyes of the flavonoids family (luteolin, apigenin and flavonols) have also been identified by the same SERS method in wool fibers dyed with natural plants, mainly used in Central and South America (Dyer's greenweed, old fustic, onion and chilca) following pre-Columbian dying recipes. Copyright © 2010 John Wiley & Sons, Ltd.
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surface enhanced raman scattering study of the adsorption of the anthraquinone pigment Alizarin on ag nanoparticles
Journal of Raman Spectroscopy, 2004Co-Authors: Maria Vega Canamares, Jose Vicente Garciaramos, Concepcion Domingo, Santiago SanchezcortesAbstract:FT-Raman and surface-enhanced Raman scattering (SERS) spectroscopy were applied in the vibrational characterization and study of the adsorption and acidity behavior of the highly fluorescent anthraquinone dye Alizarin on Ag colloids prepared by chemical reduction with hydroxylamine hydrochloride. The SERS spectra were obtained at different conditions of pH, excitation wavelength and pigment concentration in order to deduce the adsorption mechanism of this molecule. On the basis of the results found we propose an adsorption model for Alizarin, which has a different acidic behavior on the metal surface to that in solution. On the metal the deprotonation order of the OH groups changes with respect to the aqueous solution, the OH in position 1 being the first to be ionized instead of that in position 2 as occurs in solution. The two main Alizarin forms identified on the metal surface correspond to the mono- and dianionic Alizarin species. Copyright © 2004 John Wiley & Sons, Ltd.
Concepcion Domingo - One of the best experts on this subject based on the ideXlab platform.
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extractionless non hydrolysis surface enhanced raman spectroscopic detection of historical mordant dyes on textile fibers
Journal of Raman Spectroscopy, 2010Co-Authors: Z Jurasekova, Jose Vicente Garciaramos, Santiago Sanchezcortes, E Del Puerto, G Bruno, Concepcion DomingoAbstract:Alizarin and carminic acid have been detected in reference wool and linen fibers dyed with madder and cochineal, respectively, through surface-enhanced Raman scattering (SERS) measurements carried out directly on the fiber, without previous hydrolysis of the mordant-dye complex. For such purpose, Ag nanoparticles were produced and immobilized in situ via the laser photoreduction of a silver nitrate aqueous solution in contact with the fiber. Control SERS spectra of pure dyes (Alizarin, purpurin and carminic acid, as well as of mixtures of the first two) on similar Ag nanoparticles were also obtained. The method has been applied to one archeological Coptic textile (6th–8th A.D.) of Egyptian origin, where Alizarin has been clearly identified. Other mordant dyes of the flavonoids family (luteolin, apigenin and flavonols) have also been identified by the same SERS method in wool fibers dyed with natural plants, mainly used in Central and South America (Dyer's greenweed, old fustic, onion and chilca) following pre-Columbian dying recipes. Copyright © 2010 John Wiley & Sons, Ltd.
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surface enhanced raman scattering study of the adsorption of the anthraquinone pigment Alizarin on ag nanoparticles
Journal of Raman Spectroscopy, 2004Co-Authors: Maria Vega Canamares, Jose Vicente Garciaramos, Concepcion Domingo, Santiago SanchezcortesAbstract:FT-Raman and surface-enhanced Raman scattering (SERS) spectroscopy were applied in the vibrational characterization and study of the adsorption and acidity behavior of the highly fluorescent anthraquinone dye Alizarin on Ag colloids prepared by chemical reduction with hydroxylamine hydrochloride. The SERS spectra were obtained at different conditions of pH, excitation wavelength and pigment concentration in order to deduce the adsorption mechanism of this molecule. On the basis of the results found we propose an adsorption model for Alizarin, which has a different acidic behavior on the metal surface to that in solution. On the metal the deprotonation order of the OH groups changes with respect to the aqueous solution, the OH in position 1 being the first to be ionized instead of that in position 2 as occurs in solution. The two main Alizarin forms identified on the metal surface correspond to the mono- and dianionic Alizarin species. Copyright © 2004 John Wiley & Sons, Ltd.
Hlavatovičová Eva - One of the best experts on this subject based on the ideXlab platform.
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Nanočástice citlivé na vnější podněty obsahující fenylboronové spojky jako potenciální nosiče léčiv
Univerzita Karlova Přírodovědecká fakulta, 2020Co-Authors: Hlavatovičová EvaAbstract:This thesis deals with the post-polymerization functionalization of a pH-responsive poly(styrene)-b-poly(4-vinyl pyridine)-b-poly(ethylene oxide) triblock terpolymer with stimuli responsive and diol-binding 2-bromomethyl-4-fluorophenylboronic acid and 2- bromomethyl-phenylboronic acid suitable for biomedical applications. A reproducible method of quaternization of poly(4-vinyl pyridine) block with prescriptible quaternization ratio was developed and the reaction yield was analyzed by 11 B, 1 H NMR and infrared spectroscopy. A reproducible self-assembly protocol for stable nanoparticles from functionalized stimuli-responsive triblock terpolymer was found, and the nanoparticles were studied by static, dynamic and electrophoretic light scattering, and cryogenic transmission electron microscopy. Fluorescence and UV-VIS spectroscopy measurements were performed for description of boron-ester linkages formation and hydrolysis with model drug Alizarin as a study of encapsulation and release reactions together with sugar sensing reactions for potential drug delivery.Diplomová práce se zabývá přípravou polymerních systémů citlivých na vnější podněty pro medicínské aplikace založených na postpolymerizační funkcionalizaci trojblokového terpolymeru poly(styren)-b-poly(4-vinyl pyridin)-b-poly(ethylen oxid) pomocí funkčních skupin schopných vázat dioly 2-bromethyl-4-fluorofenylboronovou kyselinou a 2-bromethyl-fenylboronovou kyselinou. Byl vyvinut plně reprodukovatelný a kontrolovatelný postup kvaternizace N-skupiny 4-pyridinylového kruhu uvedenými funkčními skupinami a výtěžek kvaternizační reakce byl určen pomocí 11 B a 1 H NMR a infračervené spektroskopie. Dále byl vypracován protokol reprodukovatelné přípravy stabilních polymerních nanočástic ve vodných pufrech o různém pH vzniklých samoskládáním těchto funkcionalizovaných trojblokových terpolymerů. Struktura a chování připravených nanočástic byly studovány pomocí statického, dynamického a elektroforetického rozptylu světla a kryogenní transmisní elektronové mikroskopie. S ohledem na možné aplikace byl pomocí absorpční a fluorescenční spektroskopie zkoumána vazba modelového léčiva Alizarinu na fenylboronové funkční skupiny připravených nanočástic. Byla důkladně studována vazba Alizarinu na polymerní částice a jeho uvolňování vlivem změny vnějších podmínek jako pH a koncentrace cukrů a příbuzných diolůDepartment of Physical and Macromolecular ChemistryKatedra fyzikální a makromol. chemiePřírodovědecká fakultaFaculty of Scienc
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Nanočástice citlivé na vnější podněty obsahující fenylboronové spojky jako potenciální nosiče léčiv
Univerzita Karlova Přírodovědecká fakulta, 2020Co-Authors: Hlavatovičová EvaAbstract:Diplomová práce se zabývá přípravou polymerních systémů citlivých na vnější podněty pro medicínské aplikace založených na postpolymerizační funkcionalizaci trojblokového terpolymeru poly(styren)-b-poly(4-vinyl pyridin)-b-poly(ethylen oxid) pomocí funkčních skupin schopných vázat dioly 2-bromethyl-4-fluorofenylboronovou kyselinou a 2-bromethyl-fenylboronovou kyselinou. Byl vyvinut plně reprodukovatelný a kontrolovatelný postup kvaternizace N-skupiny 4-pyridinylového kruhu uvedenými funkčními skupinami a výtěžek kvaternizační reakce byl určen pomocí 11 B a 1 H NMR a infračervené spektroskopie. Dále byl vypracován protokol reprodukovatelné přípravy stabilních polymerních nanočástic ve vodných pufrech o různém pH vzniklých samoskládáním těchto funkcionalizovaných trojblokových terpolymerů. Struktura a chování připravených nanočástic byly studovány pomocí statického, dynamického a elektroforetického rozptylu světla a kryogenní transmisní elektronové mikroskopie. S ohledem na možné aplikace byl pomocí absorpční a fluorescenční spektroskopie zkoumána vazba modelového léčiva Alizarinu na fenylboronové funkční skupiny připravených nanočástic. Byla důkladně studována vazba Alizarinu na polymerní částice a jeho uvolňování vlivem změny vnějších podmínek jako pH a koncentrace cukrů a příbuzných diolůThis thesis deals with the post-polymerization functionalization of a pH-responsive poly(styrene)-b-poly(4-vinyl pyridine)-b-poly(ethylene oxide) triblock terpolymer with stimuli responsive and diol-binding 2-bromomethyl-4-fluorophenylboronic acid and 2- bromomethyl-phenylboronic acid suitable for biomedical applications. A reproducible method of quaternization of poly(4-vinyl pyridine) block with prescriptible quaternization ratio was developed and the reaction yield was analyzed by 11 B, 1 H NMR and infrared spectroscopy. A reproducible self-assembly protocol for stable nanoparticles from functionalized stimuli-responsive triblock terpolymer was found, and the nanoparticles were studied by static, dynamic and electrophoretic light scattering, and cryogenic transmission electron microscopy. Fluorescence and UV-VIS spectroscopy measurements were performed for description of boron-ester linkages formation and hydrolysis with model drug Alizarin as a study of encapsulation and release reactions together with sugar sensing reactions for potential drug delivery.Department of Physical and Macromolecular ChemistryKatedra fyzikální a makromol. chemieFaculty of SciencePřírodovědecká fakult
Tuan Vodinh - One of the best experts on this subject based on the ideXlab platform.
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application of surface enhanced raman scattering sers for the identification of anthraquinone dyes used in works of art
Journal of Raman Spectroscopy, 2006Co-Authors: Kui Chen, Marco Leona, Kimchi Vodinh, Fei Yan, Musundi B Wabuyele, Tuan VodinhAbstract:Surface-enhanced Raman scattering (SERS) was investigated for applications in the analysis of anthraquinone dyes used in works of art. Two SERS procedures were developed and evaluated with three frequently used anthraquinone dyes, Alizarin, carminic acid and lac dye. The first procedure involves coating a layer of silver nanoparticles directly on pieces of filter paper stained with the dyes of interest by thermal evaporation to induce SERS effect. In the second procedure, a SERS-active Ag-Al{sub 2}O{sub 3} substrate was prepared by spin-coating an alumina-nanoparticle layer onto a glass slide to provide the nanostructure of the substrate, followed by thermally evaporating a layer of silver nanoparticles on top of the alumina layer. Aliquots of dye solutions were delivered onto this substrate to be analyzed. Intense SERS spectra characteristic of Alizarin, carminic acid and lac dye were obtained using both SERS procedures. The effects of two parameters, the concentration of the alumina suspension and the thickness of the silver nanoparticle layer on the performance of the Ag-Al{sub 2}O{sub 3} substrate were examined with Alizarin as the model compound. Comparative studies were conducted between the Ag-Al{sub 2}O{sub 3} substrate and the SERS substrate prepared using Tollens reaction. The Ag-Al{sub 2}O{sub 3} substrate was shownmore » to offer larger enhancement and improved reproducibility than the Tollens substrates. Finally, the potential applicability of the Ag-Al{sub 2}O{sub 3} substrate for the analysis of real artifact objects was illustrated by the identification of Alizarin extracted from a small piece of textile dyed using traditional methods and materials. The limit of detection for Alizarin was estimated to be 7 x 10{sup -15} g from tests performed on solutions of known concentration.« less
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application of surface enhanced raman scattering sers for the identification of anthraquinone dyes used in works of art
Advanced environmental chemical and biological sensing technologies. Conference, 2005Co-Authors: Kui Chen, Marco Leona, Kimchi Vodinh, Fei Yan, Musundi B Wabuyele, Tuan VodinhAbstract:Surface-enhanced Raman scattering (SERS) was investigated for applications in the analysis of anthraquinone dyes used in works of art. Two SERS procedures were developed and evaluated with frequently used anthraquinone dyes, Alizarin, carminic acid and lac dye. The first procedure involves the removal of a microscopic fragment containing Alizarin from a painting, and a layer of silver nanoparticles was thermally evaporated directly on the fragment to induce SERS signal from Alizarin. The applicability of this procedure for analyzing solid samples of color layer from paintings was discussed in detail. In the second procedure, a SERS-active substrate was prepared by spin-coating an alumina-nanoparticle layer onto a glass slide, followed by thermally evaporating a layer of silver nanoparticles on top of the alumina layer. Aliquots of dye solutions were delivered onto this substrate where intense SERS spectra characteristic of Alizarin, carminic acid, and lac dye were obtained. The effects of two parameters, the concentration of the alumina suspension, and the thickness of the silver nanoparticle layer, on the performance of the Ag-Al 2 O 3 substrate were examined with Alizarin as the model compound. Comparative studies with other common SERS substrates showed larger enhancement and improved reproducibility for the Ag-Al 2 O 3 substrate. The potential applicability of the Ag-Al 2 O 3 substrate for the analysis of real artifact objects was illustrated by the identification of Alizarin extracted from a small piece of textile dyed with traditional methods and materials. The limit of detection for Alizarin was estimated to be 7x10 -15 g from tests using solutions of known concentration.