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1
Lefley, Colin Richard. "Raman spectroscopic studies of porphyrins and porphyrin-protein complexes". Thesis, University of York, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239782.
Testo completo
2
Krivokapic, Alexander. "Porphyrins and expanded porphyrins for optical limiting". Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270203.
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3
Mori, Goro. "Exploration of Porphyrins and Expanded Porphyrins with Novel Properties". 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/124357.
Testo completo
4
Sek, Sau Yin. "The synthesis of haematoporphyrin derivative III and other novel porphyrins /". Title page, table of contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phs4622.pdf.
Testo completo
5
Meshkov, Ivan. "Control of molecular movement based on porphyrins". Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAF006/document.
Testo completoAbstract (sommario):
Les travaux décrits dans ce manuscrit s’intéressent au contrôle du mouvement moléculaire. Après une introduction dédiée à l’état de l’art des machines moléculaires, le premier chapitre s’intéresse à la conception de tourniquets moléculaires à base de complexes porphyriniques de P(V). Le mouvement moléculaire a pu être contrôlé de manière réversible soit par l’utilisation des sites de coordination présents à la périphérie du système soit par des variations de pH. Le deuxième chapitre s’intéresse aux propriétés photophysiques des porphyrines de P(V) obtenues et plus particulièrement à leur capacité à générer de l’oxygène singulet avec une application potentielle en Thérapie Photodynamique (PDT).Le troisième chapitre concerne l’élaboration d’un complexe contenant deux porphyrines de Zn(II) dont le mouvement relatif a pu être bloqué réversiblement par l’utilisation des positions axiales des cations métalliquesThe manuscript focuses on molecular machines and the control of their movement. Two different devices have been designed, synthetized and characterized. Moreover, a series of new potential photosensitizer was obtained.The introduction gives a general overview on molecular machines, reported during the past 20 years. The first chapter describes the synthesis of molecular turnstiles based on P(V) porphyrins. The molecular motion was controlled reversibly using either coordination chemistry or by changing the pH. The second part is dedicated to the study of the photophysical properties of P(V) porphyrins and especially their capacity to generate singlet oxygen under irradiation., making them potential photosensitizers that can be use in Photodynamic Therapy (PDT) or as catalyst. The third chapter is devoted to the study of a molecular break based on a Zn (II) porphyrin dimer. The control of the movement was performed using the coordination of a bidentate ligand in the axial position of the metal cations
6
Burgess, Robert Marshall. "Ambient gas effects on thin film porphyrins and on Al/Porphyrin/Ag electroluminescent and electrochemical devices /". Thesis, Connect to this title online; UW restricted, 1986. http://hdl.handle.net/1773/11579.
Testo completo
7
Davis, Nicola Kathleen Sybille. "Anthracene-fused porphyrins". Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:86b0efea-d33a-42e2-9304-82d94e8f895a.
Testo completoAbstract (sommario):
This thesis describes the synthesis of a novel family of porphyrins fused to anthracenes, together with investigations into their optical and electrochemical properties, as well as exploring their potential for application in dye-sensitised solar cells. Chapter 1 gives an overview of the structure-property relationships of large planar pi- systems for organic electronic applications. Porphyrins are introduced as suitable building blocks for such systems, and approaches for extending the pi-conjugation of these macrocycles are presented. A literature review of porphyrins fused to aromatic units is presented in Chapter 2, with a focus on the influence of structure on the optoelectronic properties of such systems. The chapter concludes with a summary of my previous work on the synthesis of anthracene-fused porphyrins, and the aims of this project are stated. Chapter 3 describes the syntheses of fully and partially fused bis-anthracene porphyrin monomers and dimers. By varying peripheral substituents, it was possible to solve problems of aggregation encountered for these systems. Fusion of anthracene units to a porphyrin core was found to result in systems displaying strong absorption in the near-IR, small HOMO-LUMO gaps, and low oxidation potentials. Chapter 4 explores the synthesis, crystal structure and optoelectronic properties of a porphyrin fused to four anthracenes, revealing this system to exhibit the longest wavelength absorption of any porphyrin monomer. The synthesis of a liquid crystalline tetra-anthracene-fused porphyrin was proposed, and attempts to synthesise the necessary anthracene precursors were undertaken. Chapter 5 describes the molecular design and synthetic pathway to a mono-anthracene fused porphyrin, and its unfused analogue, for use in liquid electrolyte dye-sensitised solar cells. By varying the metal oxide layer or lithium ion concentration of the device, it was possible to achieve incident photon to current conversion efficiency (IPCE) responses at wavelengths beyond 1050 nm. Chapter 6 details the experimental synthetic procedures and characterisation data for all the compounds synthesised during this project.
8
Locos, Oliver Brett. "Synthesis and investigations of novel alkenylporphyrins and bis(porphyrins)". Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16409/1/Oliver_Locos_Thesis.pdf.
Testo completoAbstract (sommario):
Twelve porphyrin dyads linked by an ethene bridge were synthesised as model
systems for conjugated polymers. The extent of interporphyrin interaction was
investigated for meso-meso and meso-β linked homo- and heterobimetallo-porphyrin
dyads. To complement these dyads, model monomers with alkenyl substituents were
also studied. Once the synthesis of these compounds was achieved, the extent of
interaction was studied using UV-visible and fluorescence spectroscopy and
molecular modelling.
In order to gain a true indication of the extent of interaction in a dyad, the effect of
the bridge as a substituent must be accounted for. This was achieved by studying the
series of monomers by UV-visible and fluorescence spectroscopy. The increased
conjugation resulting from mono- and bis-alkenyl substituents results in a red shift of
the origin of transition energies in the absorption spectrum which is accompanied by
a broadened and less intense Soret band and an increase in the intensity of the Q
bands. The emission of these compounds also displays an increase in Stokes shift and
a loss of vibronic coupling due to the increased conjugation.
The serendipitous synthesis of three asymmetric meso-β ethene-linked porphyrin
dyads was achieved by the use of palladium-catalysed Heck coupling of mesoethenyl-
with meso-bromoporphyrins. A possible mechanism for this meso to β
rearrangement was proposed. A series of nine meso-meso ethene-linked dyads was
synthesised by palladium-catalysed Suzuki coupling of meso-(2-iodoethenyl)- with
meso-borolanylporphyrins. All of these dyads were characterised by 1D and 2D
NMR as well as MS analysis. The absorption spectra of ethene-linked dyads exhibit
a split Soret band and a red-shifted and intensified HOMO-LUMO band. In the
meso-β dyads, the degree of splitting in the Soret band is sufficient only to generate a
shoulder on the red edge, whereas in the meso-meso dyads two separate bands
appear. The extent of splitting is believed to be an indication of the amount of
porphyrin-porphyrin interaction.
The fluorescence profiles of the dyads change dramatically depending upon the
central substituents in the porphyrins and the wavelength used for irradiation, which suggests that different conformations of these compounds give rise to different parts
of their absorption and emission profiles. The fluorescence profiles of the dyads also
do not reflect their absorption profiles, and therefore the excitation of the dyad is
believed to be accompanied also by a change in geometry. All ethene-linked dyads
exhibited an anti-Stokes shift, and the excitation spectra of the different parts of the
fluorescence envelope also support the possibility of different conformers
contributing to the fluorescence spectra.
Molecular mechanics and time-dependent quantum mechanical calculations were
performed on seven ethene-linked porphyrin dyads. These calculations further
support the proposal of different conformations contributing to the physical
properties of ethene-linked dyads. Electronic structure calculations also show
considerable electron density on the alkene for the meso-meso ethene-linked dyads,
which highlights the important influence of this bridge upon the electronic nature of
these conjugated diporphyrins.
9
Locos, Oliver Brett. "Synthesis and investigations of novel alkenylporphyrins and bis(porphyrins)". Queensland University of Technology, 2006. http://eprints.qut.edu.au/16409/.
Testo completoAbstract (sommario):
Twelve porphyrin dyads linked by an ethene bridge were synthesised as model systems for conjugated polymers. The extent of interporphyrin interaction was investigated for meso-meso and meso-β linked homo- and heterobimetallo-porphyrin dyads. To complement these dyads, model monomers with alkenyl substituents were also studied. Once the synthesis of these compounds was achieved, the extent of interaction was studied using UV-visible and fluorescence spectroscopy and molecular modelling. In order to gain a true indication of the extent of interaction in a dyad, the effect of the bridge as a substituent must be accounted for. This was achieved by studying the series of monomers by UV-visible and fluorescence spectroscopy. The increased conjugation resulting from mono- and bis-alkenyl substituents results in a red shift of the origin of transition energies in the absorption spectrum which is accompanied by a broadened and less intense Soret band and an increase in the intensity of the Q bands. The emission of these compounds also displays an increase in Stokes shift and a loss of vibronic coupling due to the increased conjugation. The serendipitous synthesis of three asymmetric meso-β ethene-linked porphyrin dyads was achieved by the use of palladium-catalysed Heck coupling of mesoethenyl- with meso-bromoporphyrins. A possible mechanism for this meso to β rearrangement was proposed. A series of nine meso-meso ethene-linked dyads was synthesised by palladium-catalysed Suzuki coupling of meso-(2-iodoethenyl)- with meso-borolanylporphyrins. All of these dyads were characterised by 1D and 2D NMR as well as MS analysis. The absorption spectra of ethene-linked dyads exhibit a split Soret band and a red-shifted and intensified HOMO-LUMO band. In the meso-β dyads, the degree of splitting in the Soret band is sufficient only to generate a shoulder on the red edge, whereas in the meso-meso dyads two separate bands appear. The extent of splitting is believed to be an indication of the amount of porphyrin-porphyrin interaction. The fluorescence profiles of the dyads change dramatically depending upon the central substituents in the porphyrins and the wavelength used for irradiation, which suggests that different conformations of these compounds give rise to different parts of their absorption and emission profiles. The fluorescence profiles of the dyads also do not reflect their absorption profiles, and therefore the excitation of the dyad is believed to be accompanied also by a change in geometry. All ethene-linked dyads exhibited an anti-Stokes shift, and the excitation spectra of the different parts of the fluorescence envelope also support the possibility of different conformers contributing to the fluorescence spectra. Molecular mechanics and time-dependent quantum mechanical calculations were performed on seven ethene-linked porphyrin dyads. These calculations further support the proposal of different conformations contributing to the physical properties of ethene-linked dyads. Electronic structure calculations also show considerable electron density on the alkene for the meso-meso ethene-linked dyads, which highlights the important influence of this bridge upon the electronic nature of these conjugated diporphyrins.
10
Hames, Tim. "Playing Tetris with porphyrins : the synthesis of porphyrinic materials for self-sssembly studies". Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/37990/.
Testo completoAbstract (sommario):
This thesis focuses on the synthesis of porphyrinic materials for self-assembly studies. It begins with the synthesis of a large number of ‘building block’ molecules, terminated with bromo-, alkyne- and TMS- groups. These molecular building blocks are combined to form porphyrin compounds also terminated with bromo- alkyne- and TMS- groups at carefully selected positions. A series of porphyrin arrays inspired by the computer game Tetris was designed to be synthesised from these porphyrin units. The Tetris compounds are comprised of four square-like tetraphenylporphyrin (TPP) units, linked together with alkyne bridges to create arrays shaped like the T, I, L/J, S/Z and O Tetriminos. The NMR spectroscopy of the Tetris compounds is thoroughly explored to highlight the slight structural differences between the molecules. The synthesis of two bromoaryl-terminated porphyrin dimers for ultimate incorporation into covalent organic frameworks (COFs) is also described. The X-ray diffraction data collected showed that crystals grown were of trifluoroacetic acid (TFA) salts of the target compounds. The presence of the TFA anions resulted in significant distortion of the porphyrin ring which is described in full. Finally, the synthesis of a series of poly(acetylene) anthracene dimer compounds that have potential use in the field of organic electronics has also been explored. The electrochemical and fluorescence properties of the molecules across the series are investigated and the crystal structures are described.
11
Smith, Martin Joseph. "Push-pull quinoidal porphyrins". Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409762.
Testo completo
12
Jiang, Lin. "Functionalized pi-Extended Porphyrins". Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1373974099.
Testo completo
13
Ishtaiwi, Zakariyya, Tobias Rüffer, Sami Klaib, Roy Buschbeck, Bernhard Walfort e Heinrich Lang. "Porphyrins with a carbosilane dendrimer periphery as synthetic components for supramolecular self-assembly". Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-144618.
Testo completoAbstract (sommario):
The preparation of the shape-persistent carbosilane-functionalized porphyrins H2TPP(4-SiRR’Me)4, Zn(II)- TPP(4-SiRR’Me)4 (R = R’ = Me, CH2CHvCH2, CH2 CH2CH2OH; R = Me, R’ = CH2 CHvCH2, CH2CH2CH2OH; TPP = tetraphenyl porphyrin), H2TPP(4-Si(C6H4-1,4-SiRR’Me)3)4, and Zn(II)-TPP(4-Si- (C6H4-1,4-SiRR’Me)3)4 (R = R’ = Me, CH2CHvCH2; R = Me, R’ = CH2CHvCH2) using the Lindsey condensation methodology is described. For a series of five samples their structures in the solid state were determined by single crystal X-ray structure analysis. The appropriate 0th and 1st generation porphyrin-based 1,4-phenylene carbosilanes form 2D and 3D supramolecular network structures, primarily controlled by either π–π interactions (between pyrrole units and neighboring phenylene rings) or directional molecular hydrogen recognition and zinc–oxygen bond formation in the appropriate hydroxyl-functionalized molecules. UV-Vis spectroscopic studies were carried out in order to analyze the effect of the dendritic branches on the optical properties of the porphyrin ringDieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
14
Hernández, Eguía Laura P. "Supramolecular chemistry of bis-porphyrins". Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9059.
Testo completoAbstract (sommario):
(Base de datos de tesis doctorales TESEO) En este trabajo de tesis doctoral se desarrollan básicamente dos aspectos. El primero, es la síntesis de receptores bis-porfirínicos metalados con zinc, tanto acíclicos como cíclicos, y con diferente grado de saturación de las cadenas carbonadas, y el segundo, trata sobre los estudios de complejación llevados a cabo con ligandos de diferente tipo y propiedades: aminas y fullerenos. Los primeros se unen mediante enlaces de coordinación metal-nitrógeno, mientras que los segundos se basan en interacciones entre el anillo aromático de la porfirina y la estructura con un marcado carácter aromático de los fullerenos.
Además, se exponen los resultados obtenidos al derivar uno de los ciclopéptidos del grupo de investigación del Prof. J.R. Granja con una o dos porfirinas de zinc y emplear el ensamblaje supramolecular tipo "sándwich" entre bis-porfirinas y aminas ditópicas para controlar la mezcla regioisomérica que tiene lugar en el proceso de autoensamblaje entre los ciclopéptidos.
(Base de datos de tesis doctorales TESEO) English version
In this doctoral thesis two main aspects are developed. The first is the synthesis of bis-porphyrin receptors metallated with zinc, both acyclic and cyclic, and with different degrees of saturation of the carbon chain, and the second deals with the studies of complexation with ligands of different types and properties: amines and fullerenes. The first ligands are connected by metal-nitrogen coordination between the nitrogen of the ligand and the zinc of the porphyrin ring, while the latter are interactions between the aromatic ring of the porphyrin and the fullerenes.
In addition, we present the results obtained when derive one of the cyclopeptides of the research group of Prof. J.R. Granja with one or two zinc porphyrins, using the motif: "sandwich" complexes between bis-porphyrins and ditopic amines, in order to control the regioisomeric mixture that takes place in the self-assembly of the cyclopeptides.
15
Hunter, Chris. "Biomimetic supramolecules based on porphyrins". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315073.
Testo completo
16
Evans, S. D. "Langmuir-Blodgett superlattices incorporating porphyrins". Thesis, Lancaster University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235169.
Testo completo
17
Bretscher, K. R. "Redox reactions of iron-porphyrins". Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371913.
Testo completo
18
Aiken, Stuart. "Porphyrins for optical limiting applications". Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369729.
Testo completoAbstract (sommario):
A number of symmetric porphyrins containing both zinc(II) and lead(II) central metal ions have been prepared. Several routes to these compounds have been investigated and their merits evaluated. The conjugation of the chromophores has been extended by the inclusion of different trans- substituted arylethynyl substituents in the meso-position. An improved multigram method for the preparation of [bis-trimethylsilyethynylporphinato]zinc(II), which does not necessitate chromatographic purification, is described. The use of [5-triisopropylsilylethynylporphinato]zinc(II) for the preparation of donor/acceptor prophyrins via Sonogashira coupling, several of which were prepared, is also described. Investigations of the binding of 4(3H)pyrimidone with [5,5'-bis-[10,20-bis(3,5-di-tert-butylphenyl)-15-tri-iso-propylsilylethynyl-porphinyl]-1,3-butyn-1,4-diyl]dizinc(II) were made. The association constant was found to be 2500 ± 140 mol-1 (ΔG = -4.6 Kcal/mol), significantly greater than that for 4(3H)pyrimidone alone (444 ± 5 mol-1), as determined by NMR dilution experiments. The crystal structures of [5,15-bis(3,5-bis-tert-butylphenyl)porphinato]zinc(II), [5,15-bis-(3,5-di-tert-butylphenyl)-10,20-bis-triisopropylsilylethynylporphinato]lead(II), [5,10,15,20-tetrakis-triisopropylsilylethynylporphinato]lead(II), 5,15-bis-(3,5-bis-tert-butylphenyl)-10,20-bis-phenylethynylporphyrin, [5,15-bis-(3,5-bis-tert-butylphenyl)-10,20-bis-(3-hydroxy-3-methyl-butynyl)porphinato]zinc(II),5,10,15,20-tetrakis-triisopropylsilylethynylporphyrin and [5,15-bis-(3,5-bis-tert-butylphenyl)-10-(4-N, N-dimethylaminophenylethynyl)-20-triisopropylsilylethynylporphinato]zinc(II) are also described.
19
Leighton, P. "Observations on some bridged porphyrins". Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355269.
Testo completo
20
Kieran, Amy Lydia. "Dynamic combinatorial libraries of porphyrins". Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616016.
Testo completo
21
Tong, Lok Hang. "New supramolecular chemistry of porphyrins". Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614360.
Testo completo
22
Anderson, Harry Laurence. "Model enzymes based on porphyrins". Thesis, University of Cambridge, 1990. https://www.repository.cam.ac.uk/handle/1810/272953.
Testo completo
23
Costa, Liliana Andreia dos Santos. "Photoinactivation of viruses by porphyrins". Doctoral thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10869.
Testo completoAbstract (sommario):
Doutoramento em BiologiaA inativação fotodinâmica tem sido usada com sucesso na inativação de microorganismos. Diversos aspetos da inativação fotodinâmica foram já estudados para diferentes microrganismos, contudo, existe ainda pouca informação disponível no que diz respeito à inativação de bacteriófagos por processos fotodinâmicos. Este trabalho pretendeu elucidar e avaliar vários aspetos da fotoinativação de vírus, em particular de bacteriófagos, incluindo (i) o efeito de diversos parâmetros de luz utilizados na fotoinativação de bacteriófagos; (ii) a eficiência da inativação fotodinâmica de diferentes tipos de bacteriófagos (fagos do tipo DNA e RNA); (iii) o principal mecanismo através do qual a inativação fotodinâmica tem lugar; (iv) o efeito da fotoinativação nas proteínas do bacteriófago; e (v) o possível desenvolvimento de resistência e recuperação da viabilidade após vários tratamentos fotodinâmicos consecutivos. Para avaliar o efeito dos diferentes parâmetros de luz, suspensões fágicas com 107 UFP mL-1 foram irradiadas com diferentes fontes e doses de luz, intensidades luminosas e tempos de irradiação (30,90 e 270 min) na presença de 0,5; 1,0 e 5,0 μM dos derivados porfirínicos catiónicos Tri- Py+-Me-PF e Tetra-Py+-Me. A eficiência da fotoinativação de diferentes fagos do tipo DNA e RNA, foi avaliada através da irradiação da suspensão fágica com luz branca (40 W m-2) durante 270 min na presença de 0,5 e 5,0 μM do derivado porfirínico Tri-Py+-Me-PF, respetivamente para os fagos do tipo RNA e DNA. O mecanismo através do qual a fotoinativação de fagos de DNA (fago do tipo T4) e de RNA (fago Qb) tem lugar foi avaliado por exposição da suspensão fágica à luz branca com uma potência de 40 W m-2, na presença de fotossensibilizador (Tri-Py+-Me-PF e Tetra-Py+-Me) e inibidores, quer do oxigénio singuleto (azida de sódio e L-histidina) quer de radicais livres (Dmanitol e L-cisteína). Os danos nas proteínas do fago do tipo T4, induzidos pelas espécies reativas de oxigénio geradas por 5,0 μM Tri-Py+-Me-PF, foram avaliados pelo método convencional de SDS-PAGE e por espectroscopia de infravermelho. O possível desenvolvimento de resistência e recuperação da viabilidade após a inativação fotodinâmica dos bacteriófagos foi avaliado após dez ciclos consecutivos de tratamento fotodinâmico incompletos (120 min sob irradiação de luz branca a uma potência de 40 W m-2) na presença de 5,0 μM do derivado porfirínico Tri-Py+-Me-PF. Os resultados deste trabalho mostraram que (i) quando uma quantidade de energia (dose de luz) determinada foi aplicada numa suspensão fágica, a partir de uma mesma fonte irradiação, a fotoinactivação do fago foi tanto mais eficiente quanto mais baixa foi a potência luminosa aplicada; (ii) os bacteriófagos foram eficientemente inativados até ao limite de deteção (redução de 6-7 log); (ii) os fagos do tipo RNA foram inativados mais facilmente do que os fagos do tipo DNA (tempos de exposição mais curtos e com concentração de fotossensibilizador dez vezes menor do que a usada para inativar os fagos do tipo DNA); (iii) o mecanismo do tipo II (via produção de oxigénio singuleto) foi o principal mecanismo através do qual a fotoinativação dos bacteriófagos teve lugar; (iv) foi possível detectar danos no perfil proteico após tratamento fotodinâmico e a espectroscopia de infravermelho apresentou-se como uma metodologia promissora de screening para avaliação dos danos induzidos pela inativação fotodinâmica em proteínas; e (v) após dez ciclos consecutivos de tratamento fotodinâmico, o fago do tipo T4 não revelou nenhum tipo de resistência ao tratamento fotodinâmico nem recuperou a sua viabilidade. Como conclusão, a inativação fotodinâmica microbiana é uma tecnologia bastante eficaz para a fotoinativação de bacteriófagos do tipo DNA e RNA sem invólucro, a qual pode ser considerada como uma alternativa ao tratamento convencional com agentes antivíricos, mesmo com intensidades luminosas baixas, sem o risco associado de desenvolvimento de mecanismos de resistência.
Microbial photodynamic inactivation (PDI) has been successfully used to inactivate microorganisms. PDI has already been studied under different conditions for different microorganisms; however, there is still scarce information about bacteriophage inactivation by photodynamic procedures. The goal of this study was to elucidate and evaluate several aspects of viral PDI which include (i) the effect of different light sources, doses and intensities on phage inactivation; (ii) the photoinactivation efficiency on different types of bacteriophages (DNA- and RNA-type phages), (iii) the main mechanism by which phage photosensitization takes place, (iv) the effect of PDI on phage proteins; and (v) the possibility of resistance development and viability recovery after consecutive phototreatments. To evaluate the efficiency of photoinactivation, T4-like phage suspensions of 107 PFU mL-1 were exposed to different light sources(fluorescent PAR lamps, solar light and halogen lamp), and fluence rates (40 W m-2, 600 W m-2 and 1690 W m-2) during 30, 90 and 270 min in the presence of 0.5, 1.0 and 5.0 μM of the cationic porphyrin derivatives Tri-Py+-Me-PF and Tetra-Py+-Me. DNA- and RNA-type phages were exposed to white light (40 W m-2) during 270 min in the presence of Tri-Py+-Me-PF at the concentrations of 0.5 and 5.0 μM, respectively for RNA- and DNA-type phages. The mechanism of phage inactivation was evaluated for DNA- (T4-like) and RNA-type (Qb) phages, in the presence of photosensitizer (Tri-Py+-Me-PF and Tetra-Py+-Me) and singlet oxygen quenchers (sodium azide and L-histidine) and free radicals scavengers (D-mannitol and L-cysteine). The damages on T4- like phage proteins, induced by the ROS generated by Tri-Py+-Me-PF, were assessed by the conventional SDS-PAGE analysis and by IR spectroscopy. Ten consecutive and incomplete (120 min of irradiation at 40 W m-2) cycles of T4-like phage photosensitization by 5.0 μM Tri-Py+-Me-PF were also performed in order to determine the possible development of resistance and viability recovery after phage PDI. From this study it can be concluded that (i) considering the same light source and a fixed light dose, applied at different fluence rates, phage photoinactivation was significantly higher when low fluence rates were used at long irradiation times; (ii) the phages were efficiently inactivated to the detection limit (reductions of 6-7 log); (ii) RNA-type phages were much more easily inactivated than the DNA-type ones (sooner and with ten times less porphyrin concentration than that used for DNA-type phages); (iii) type II mechanism (production of singlet oxygen) was the main mechanism by which phage photosensitization took place; (iv) IR spectroscopy represents a promising and fast-screening methodology when the damages induced by photosensitization on phage proteins are to be studied; and (v) after ten consecutive photodynamic cycles, T4-like phage did not exhibit any resistance to PDI nor recovered its viability. In conclusion, viral PDI is a very efficient technology for the inactivation of non-enveloped DNA- and RNA-type phages, which may be used as an alternative to the conventional antiviral treatments, even at low light fluence rates, without the problem of viral resistance.
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Boyett, Robin Ernest. "Computational studies of hydrophobic porphyrins". Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241621.
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Day, Nicholas Upton. "Polymeric Porphyrins as Solar Photocatalysts". PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2625.
Testo completoAbstract (sommario):
Research concentrated on the absorption, transformation, and storage of light energy is useful for the energy challenges faced by humanity. In particular, photocatalysis using solar energy to generate useful fuels has become a primary research goal in the drive to replace fossil fuels for the future. In this dissertation it is shown that poly-tetra(4-aminophenyl)porphyrin (pTAPP) can be oxidatively polymerized using a variety of methods, including electropolymerization, chemical oxidation, and interfacial polymerization and that pTAPP has photocatalytic ability to reduce O2 to H2O2 for a storable fuel.
Organic conductive polymers such as pTAPP are attractive catalysts because of their high surface area and ability to coat electrodes. pTAPP in a mixed oxidation state is shown to have both its minimum charge transfer resistance as well as its minimum impedance to electronic conductivity in the film. The UV-vis-NIR absorption spectra of pTAPP with increased oxidative doping are similar to hyperporphyrin spectra, characteristic of a two-plus charge localized on a single porphyrin unit. This suggests the presence of a bipolaron on the individual porphyrin units, and thus a bipolaron conductivity mechanism has been proposed.
pTAPP changes color depending on its oxidation state, and therefore is a promising material for electrochromic devices. A novel Pourbaix diagram was created as a means of illustrating the redox and protonation states of pTAPP as a function of changes in pH, applied potential, electrochromic behavior, and electronic conductivity.
Both pTAPP and pCoTAPP were shown to be effective catalysts for the reduction of oxygen to hydrogen peroxide, with pCoTAPP a better catalyst than pTAPP. When pCoTAPP is irradiated, oxygen reduction occurs close to the thermodynamic potential, indicating a promising system for storage of solar energy.
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Clarke, Suzanne Elizabeth. "The Effect of Two Viologens on the Solution Speciation of Tetrakis([rho]-carboxyphenyl)porphine". PDXScholar, 1990. https://pdxscholar.library.pdx.edu/open_access_etds/1372.
Testo completoAbstract (sommario):
Porphyrins and viologens are often utilized in photocatalyzed electron transfer chemistry. Some of the problems faced by researchers in these applied studies include the lack of information correlating the porphyrin absorbance spectral changes with porphyrin dimerization, complexation, and the effect of noncomplexing cations. In addition, the efficiency of the system is greatly reduced by the formation of porphyrin:viologen association complexes. Knowledge of the values of these constants may allow selection of appropriate porphyrin:viologen concentration ratios which would enable optimization of these systems when used in such applications as artificial photosynthesis. This study reports the effect of selected salts and solvents on the porphyrin spectrum and the spectrum of the H₂TCPP⁴⁻ dimer. Moreover, we define experimental conditions appropriate to the study of porphyrin:viologen association and report association constants calculated at both constant ionic strength and constant buffer concentration. The spectrophotometric titration of tetrakis(pcarboxyphenyl) porphine (H₂TCPP⁴⁻) with either methyl viologen (MV²⁺) or propylviologen sulfonate (PVS⁰) results in the formation of H₂TCPP⁴⁻ :viologen complexes with stoichiometries of both 1:1 and 1:2. In addition, at high viologen concentration, PVS⁰ induces H₂TCPP⁴⁻ dimerization. Association constants for the titration of H₂TCPP⁴⁻ with MV²⁺ were calculated using data obtained at constant ionic strength (I = 0.15, maintained with KH₂P0₄/NaKHP0₄) and at constant buffer concentration ([KH₂P0₄/NaKHP0₄] = 5 mM) using both nonlinear least-squares (NLLS) and principal component analysis (PCA). At constant buffer concentration the association constants calculated via NLLS analysis and PCA were found to be, respectively, 3,170 and 3,350 for the 1:1 complex and 100 and 68 for the 2:1 complex. At constant ionic strength the association constants were calculated by NLLS to be 594 for the 1:1 complex and 38 for the 2:1 complex. PCA was used to confirm our model of the solution equilibrium equations used to calculate the association constants by NLLS analysis. In addition, this method yields the spectral line shape and absorptivity of the spectroscopically unresolved 1:1 H₂TCPP⁴⁻:MV²⁺ complex. From this information it was learned that both the absorptivity and the wavelength dependence of H₂TCPP⁴⁻ and the viologen complexes of H₂TCPP⁴⁻ were a function of the alkali metal cation concentration (higher concentrations of cations result in progressively weakened and blue-shifted spectra). Finally, we will present data which support the conclusion of Firman et al. that the spectrum of the H₂TCPP⁴⁻ dimer is weakened and blueshifted by approximately 10 nm relative to the porphyrin monomer in aqueous solution. We will further show that some organic ions induce H₂TCPP⁴⁻ dimerization and some do not; moreover, we will present experimental evidence demonstrating that the data cannot be explained as a simple effect of the ionic strength.
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劉純晶 e Chunjing Liu. "Nonplanar and sterically encumbered ruthenium porphyrins and catalyticreactivity of ruthenium and manganese porphyrin complexes supported onMCM-41". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237423.
Testo completo
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Somma, Maria Salvatrice. "Novel methodologies for the synthesis of porphyrins and chlorins and spectroscopic studies of nonplanar porphyrins /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
Testo completo
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Wang, Chenyi. "Spectroscopy, NMR, and Electrochemistry Studies of Protonated Aminophenyl/Pyridyl Porphyrins and Their Application in Hydrogen Evolution". PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2223.
Testo completoAbstract (sommario):
Spectrophotometric titrations for a full series of 4-aminophenyl/4-pyridyl meso-substituted porphyrins were carried out using methanesulfonic acid in DMSO to study the hyperporphyrin effect across different substitution patterns. The series included zero, one, two (cis and trans), three, and four meso(4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups. The peripheral pyridyl groups consistently protonate before the interior porphyrin pyrrole nitrogens, which protonate before the aminophenyl groups. Aminophenyl substituents increase the basicity of the pyrrole nitrogens and lead to distinctive hyperporphyrin spectra with a broad Soret band and a strong red absorption. The structure proposed to give rise to these spectra is the previously proposed charge-transfer interaction between the aminophenyl and the protonated pyrrole. A novel hyperporphyrin structure involving charge-transfer interactions between two peripheral substituents is also proposed in one case - the triply protonated (+3) porphyrin with three aminophenyl and one pyridyl substituents; two of the aminophenyl groups delocalize the charges on the interior nitrogens while the third aminophenyl group delocalizes with the protonated pyridyl.
The NMR titrations for a full series of 4-aminophenyl/4-pyridyl meso-substituted porphyrins were also performed by methanesulfonic acid in DMSO. Zero, one, two (cis), three, and four meso(4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups are the primary compounds studied here. The inductive effect of the meso-substituents and the π system of the macrocycle both determine the hyperporphyrin spectra, in which inductive effect has stronger influence on cis-A2Py2P and APy3P. TAPP and A3PyP both show slow exchanges from free base to hyperporphyrin, indicating these hyperporphyrin structures are stable. Both 1H-NMR and 2D NOESY spectra further validate the existence of the novel D-type hyperporphyrin from A3PyPH3+3.
Electrochemical studies of these hyperporphyrins were also performed. The porphyrins involved here are zero, two (cis & trans), three, and four meso (4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups. The acid titrations were done in DMSO using methanesulfonic acid. Both TAPP and A3PyP can be extensively reduced with up to five distinct reduction waves. The hyperporphyrin from A3PyP, unlike that from TAPP, shows stable structures during the reduction, and A3PyPH3+3 was proposed to have the ability to reduce protons into hydrogen in a catalytic cycle.
30
Mori, Hirotaka. "Studies on Novel π-Extended Porphyrins". 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215337.
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Pearce, Wayne Ashley. "Synthetic studies towards novel annulated porphyrins /". Title page, table of contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09php3598.pdf.
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Jagessar, Raymond C. "Anion recognition by novel functionalised porphyrins". Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363767.
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Al-Obaidi, Ala. "Synthesis and laser spectroscopy of porphyrins". Thesis, University of York, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290870.
Testo completo
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Zheng, Xi. "Characterisation of luminescent electropolymerised substituted porphyrins". Thesis, Glasgow Caledonian University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443219.
Testo completo
35
Vulpe, Elena. "Molecular tectonics based on fluorinated porphyrins". Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF048/document.
Testo completoAbstract (sommario):
Les travaux décrits dans ce manuscrit utilisent les principes de la tectonique moléculaire pour générer des polymères de coordination hautement fluorés et /ou chiraux pour une application potentielle en séparation chirale. La synthèse de 13 porphyrines de type A2B2 substituées en position méso par deux pyridines et par deux chaines fluorées et/ou alkyles a été mise au point. Des réseaux de coordination ont été obtenus en présence de Zn(II) et de Cd(II) et caractérisés par diffraction des RX sur monocristal (DRX). Une analyse systématique des interactions supramoléculaires et notamment de interactions F---F présentes à l’état solide a été conduite. Des réseaux à base de liaisons halogènes ont également été obtenus en présence de di- et tri-iodoarènes et caractérisés par DRX.Le premier chapitre est une introduction générale sur la tectonique moléculaire, le deuxième chapitre décrit les voies des synthèses utilisées pour générer les ligands chiraux et fluorés et leur caractérisation à l’état solide. Le troisième chapitre présente la structure des réseaux mono, bi, et tridimensionnels formés en présence de Zn(II) ou de Cd(II), l’analyse structurale met en évidence un nombre croissant d’interaction F---F en fonction du nombre de fluors présents à la périphérie du macrocycle porphyrinique. Le dernier chapitre se concentre sur l’utilisation des liaisons halogènes de type N---I impliquant des porphyrines ou des tectons de type bipyridine et une série d’ iodofluoroarenesThis manuscript focuses on the use of molecular tectonics to generate chiral and / or fluorinated coordination polymers based on porphyrin building blocks for potential application in chiral separation. Synthesis of novel A2B2 fluorinated porphyrin tectons is described and their combinations with metal ions and haloarenes molecules are characterized by X-Ray diffraction.The first chapter gives a general introduction on molecular tectonics; the second chapter focuses on the synthetic routes used for the synthesis of highly fluorinated and/or chiral porphyrins and their solid state characterization by X-Ray diffraction analysis, highlighting the importance of the number of fluorine atoms present at the periphery of the tecton on the crystal packing. The third chapter presents the mono-, bi- and three dimensional networks formed by a combination of the porphyrins with Zn(II) or Cd(II). In the solid state, short F---F contacts were observed depending on the number of fluorine atoms present on the porphyrin backbone. The last chapter focuses on the use of halogen bonds, by merging the neutral porphyrin or bipyridine tectons with a series of iodofluoroarenes. The crystalline materials described in this work can be used as potential candidates for the separation of chiral and fluorinated molecules
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Fukui, Norihito. "Development of Novel π-Extended Porphyrins". Kyoto University, 2018. http://hdl.handle.net/2433/232280.
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Shi, Limiao. "Organic and Organometallic Porphyrins for Optics". Thesis, Rennes, INSA, 2019. http://www.theses.fr/2019ISAR0015.
Testo completoAbstract (sommario):
Au cours de ce travail de thèse, nous nous sommes concentrés sur la synthèse et la caractérisation de nouveaux composés à base de porphyrine. Ces architectures moléculaires ont été élaborées pour leurs propriétés optiques linéaires (OL) et non linéaires (ONL), particulièrement pour leurs propriétés d'absorption à deux photons (ADP). Les processus de transfert d'énergie des bras donneurs vers le cœur porphyrine sont aussi discutés. Tout d'abord, en Introduction (Chapitre I), nous présentons le contexte général de la chimie des porphyrines selon cinq aspects: (1) la structure, (2) les méthodes de synthèse, (3) les propriétés en OL et (4) les propriétés en ONL (5) la thérapie photodynamique (PDT). Nous avons aussi brièvement reporté les travaux antérieurs de notre groupe sur ce sujet puis proposé de nouvelles molécules, basées sur ces résultats. Dans le second chapitre, une série de porphyrines contenant des bras fluorényles liés par des liaisons double, avec des longueurs croissantes, a été préparée et étudiée. Ces composés ayant des propriétés optiques intéressantes, montrent que l’extension de la longueur des bras fluorényles permet d’améliorer les sections efficaces d’ADP. À la fin de ce chapitre II, nous présentons la synthèse de la porphyrine en forme d’étoile, la plus étendue de la série, possédant cinq fluorényles reliés par des doubles liaisons. Les études d’optiques sont en cours. Dans le chapitre III, composé de deux parties : (i) Nous avons commencé par la synthèse d'une série de porphyrines avec du carbazole et de la diphénylamine comme groupes terminaux ou comme points de jonction de dendrimères. Leurs propriétés optiques ont été étudiées et montrent que les porphyrines avec la diphénylamine sont les plus efficaces; (ii) Compte tenu de ces résultats; nous avons alors concentré nos efforts sur la synthèse de porphyrines en forme d'étoile possédant des bras fluorényles avec des liaisons vinyle et alcynyle et décorées avec la diphénylamine. Dans le chapitre IV, tourné vers les applications médicales, pour la première fois nous avons élaboré des fluorényl-porphyrines portant des chaînes hydrophiles et aussi des sucres pour la thérapie cancéreuse (2P PDT). En collaboration avec le Dr Gary-Bobo des résultats de photosensibilisation et de biocompatibilité ont été obtenus in vitro sur des cellules cancéreuses, il a été montré que ces molécules étaient efficaces pour l'imagerie par fluorescence et aussi pour la thérapie. Dans le dernier chapitre de ce travail (chapitre V), une série de porphyrines organométalliques fonctionnalisées en périphérie avec des antennes linéaires ou dendritiques, décorées d’acétylures de ruthénium a été préparée. Afin d’optimiser les propriétés ONL, nous avons étudié trois stratégies pour étendre le système π de ces antennes, notamment (i) avec des doubles liaisons (ii) avec des groupes terminaux donneurs (iii) en utilisant des structures dendrimères. Les études d’optiques de ces nouvelles porphyrines organométalliques sont en coursDuring this thesis, we have focused on the synthesis and characterization of new compounds using the porphyrin macrocycle as the base of our structures. These new molecular architectures were elaborated for their linear (LO) and nonlinear optical (NLO) properties, especially their two-photon absorption properties (2PA). Their energy transfer processes from the donor arms to porphyrin core are also discussed. First of all, as an Introduction (Chapter I) we present the general background of the porphyrin chemistry based on five aspects: (1) structure, (2) synthetic methods, (3) LO properties and (4) NLO properties (5) PDT therapy. We further reviewed prior porphyrin studies done in our group and proposed new molecular designs based on these results. In the second chapter, a series of new porphyrins containing double bonded connected fluorenyl arms, with increasing lengths, were prepared and studied. These compounds present interesting optical properties, showing that the extension of the fluorenyl antennae can enhance the 2PA cross-sections. At the end of this Chapter II, as perspective; we propose the synthesis of our most extended star shaped porphyrin; going to five fluorenyl units, the optical studies are in progress. Next, chapter III is divided in two parts: (i) we started out by the synthesis of a series of porphyrins with carbazole and diphenylamine as endgroups or as dendrimer junction points. Their optical properties were studied and obviously porphyrins with diphenylamine are the most efficient; (ii) Given these results; we focused our efforts on the synthesis of star shaped porphyrins possessing fluorenyl arms with vinyl and alkynyl connections and decorated with diphenylamine endgroups. In Chapter IV, we focused on medical applications; so porphyrins bearing water solubilizing chains, as well as sugar for cancer therapy (2P PDT) were synthesized for the first time in this work. In collaboration with Dr. Gary-Bobo, photosensitization and biocompatibility studies have been done and these porphyrins show to be efficient nontoxic 2P photosensitizers allowing also fluorescence imaging, thus demonstrating their theranostic potential. In the last chapter of this work (Chapter V), a series of organometallic porphyrins functionalized at the periphery with linear or dendritic antennae, decorated with ruthenium acetylides are prepared. In order to optimize the NLO properties, we studied three strategies to extend the π system of these antennas, notably (i) with double bonds (ii) with donor end groups (iii) using dendrimer structures. Optical studies of these new organometallic porphyrins are in progress
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Shimizu, Soji. "Development of chemistry of expanded porphyrins". 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136969.
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Soya, Takanori. "Studies on Novel Gigantic Expanded Porphyrins". Kyoto University, 2019. http://hdl.handle.net/2433/242632.
Testo completo
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IENGO, ELISABETTA. "METAL-MEDIATED SUPRAMOLECULAR ASSEMBLIES OF PORPHYRINS". Doctoral thesis, Università degli studi di Trieste, 2002. http://thesis2.sba.units.it/store/handle/item/12433.
Testo completo
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Atefi, Farzad. "Synthesis and reactions of organometallic porphyrins". Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/17563/1/Farzad_Atefi_Thesis.pdf.
Testo completoAbstract (sommario):
This thesis reports progress in three major aspects of σ-bonded organometallic porphyrins that are described in the published papers found in chapters 4, 5 and 6. meso-Iodoporphyrins, which were prepared in a rapid, selective and high yielding methodology from the respective 1-palladioporphyrins or bromoporphyrins, are important starting materials for further functionalisations of porphyrins. Their utility was confirmed in a palladium-catalysed coupling reaction and this novel synthetic strategy could potentially be applied for iodine/bromine exchange on other organic substrates..
A 1-palladioporphyrin was also utilised to optimise the reaction conditions leading to the formation of porphyrinylphosphine oxides. This synthetic strategy simplified the challenging optimisation of the palladium-catalysed reaction and has great potential to be applied in other catalytic processes. Subsequently a suite of porphyrinylphosphine oxides was prepared under the optimised catalytic conditions. These macrocycles, which represent a new class of porphyrins, were isolated cleanly in very high yields. Detailed spectroscopic investigations as well as X-ray single crystal analysis demonstrated their structures unambiguously and established their potential as ligands for supramolecular chemistry.
The coordinating properties of phosphine oxides in general and porphyrinylphosphine oxides in particular, towards Mg(II) centred porphyrins were examined in further experiments. Triphenylphosphine oxide showed a strong affinity towards Mg(II) porphyrins and the calculated displacement constant of 5.3 × 105 M-1 was two orders of magnitude larger than any other Mg(II) porphyrin-ligand binding constant reported thus far. Di- and triporphyrin arrays consisting of Mg(II) porphyrin coordinated to free base and Ni(II) porphyrinyl mono- and bis-phosphine oxides were also prepared in high yields. Spectroscopic studies indicated that these porphyrin oligomers exhibit strong inter-porphyrin electronic interaction.
A Mg(II) porphyrinylphosphine oxide dimer was also isolated in a satisfactory yield. The large self-association constant of 5.5 × 108 M-1 confirmed the strong affinity of porphyrinylphosphine oxides towards Mg(II) porphyrins and established these complexes as the first strongly bound synthetic Mg(II) porphyrin analogues of the "special pair" of the photosynthetic reaction centre.
42
Atefi, Farzad. "Synthesis and reactions of organometallic porphyrins". Queensland University of Technology, 2007. http://eprints.qut.edu.au/17563/.
Testo completoAbstract (sommario):
This thesis reports progress in three major aspects of σ-bonded organometallic porphyrins that are described in the published papers found in chapters 4, 5 and 6. meso-Iodoporphyrins, which were prepared in a rapid, selective and high yielding methodology from the respective 1-palladioporphyrins or bromoporphyrins, are important starting materials for further functionalisations of porphyrins. Their utility was confirmed in a palladium-catalysed coupling reaction and this novel synthetic strategy could potentially be applied for iodine/bromine exchange on other organic substrates..
A 1-palladioporphyrin was also utilised to optimise the reaction conditions leading to the formation of porphyrinylphosphine oxides. This synthetic strategy simplified the challenging optimisation of the palladium-catalysed reaction and has great potential to be applied in other catalytic processes. Subsequently a suite of porphyrinylphosphine oxides was prepared under the optimised catalytic conditions. These macrocycles, which represent a new class of porphyrins, were isolated cleanly in very high yields. Detailed spectroscopic investigations as well as X-ray single crystal analysis demonstrated their structures unambiguously and established their potential as ligands for supramolecular chemistry.
The coordinating properties of phosphine oxides in general and porphyrinylphosphine oxides in particular, towards Mg(II) centred porphyrins were examined in further experiments. Triphenylphosphine oxide showed a strong affinity towards Mg(II) porphyrins and the calculated displacement constant of 5.3 × 105 M-1 was two orders of magnitude larger than any other Mg(II) porphyrin-ligand binding constant reported thus far. Di- and triporphyrin arrays consisting of Mg(II) porphyrin coordinated to free base and Ni(II) porphyrinyl mono- and bis-phosphine oxides were also prepared in high yields. Spectroscopic studies indicated that these porphyrin oligomers exhibit strong inter-porphyrin electronic interaction.
A Mg(II) porphyrinylphosphine oxide dimer was also isolated in a satisfactory yield. The large self-association constant of 5.5 × 108 M-1 confirmed the strong affinity of porphyrinylphosphine oxides towards Mg(II) porphyrins and established these complexes as the first strongly bound synthetic Mg(II) porphyrin analogues of the "special pair" of the photosynthetic reaction centre.
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Liu, Chunjing. "Nonplanar and sterically encumbered ruthenium porphyrins and catalytic reactivity of ruthenium and manganese porphyrin complexes supported on MCM-41 /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19737518.
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Poon, Chun Ting. "Synthesis, characterization, photophysics, energy transfer and bioactivity of porphyrins and N-confused porphyrins with appended functional groups". HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/940.
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Wang, Yaqiong. "Synthesis of new nanomaterials based on porphyrins and graphene for elaboration of sensitive and selective DNA biosensors". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS338/document.
Testo completoAbstract (sommario):
La conception et le développement de biocapteurs pour la détection directe de biomarqueurs dans un échantillon de fluide biologique constituent un véritable défi dans la recherche pour leur application dans le système de point de soins en diagnostic. Mon projet est axé sur l'élaboration d'une nouvelle plateforme de décomposition biologique composée de graphène qui présente une surface électroactive et spécifique élevée permettant de greffer de nombreux biomolécules avec des métalloporphyrines en tant que nouveau marqueur redox pour suivre le processus de reconnaissance biologique obtenu dans le cas d'un capteur d'ADN. Le concept sera de démontrer que les métalloporphyrines où le potentiel d'oxydo-réduction pourrait être contrôlé par la nature des ions métalliques pourraient être appliquées dans une plate-forme de biocapteurs électrochimique multidétection. L'association de la métalloporphyrine avec le graphène offrira de nombreux avantages, comme la promotion de la réaction de transfert d'électrons et ayant une grande surface pour l'immobilisation des protéines. La détection de la cible présente sera réalisée suite à l'activité redox des métalloporphyrines greffées à la surface. Nous avons déjà synthétisé différentes métalloporphyrines modifiées et caractérisées par des techniques habituelles de spectrométrie telles que la RMN, les UV et la MS. Le biocapteur d'ADN a été construit par le composite de graphène et métalloporphyrine et sonde d'ADN comme biorécepteur suivant l'approche d'attachement covalent et l'optimisation de la construction de biocapteur pour améliorer la stabilité et la reproductibilité. Et nous avons déjà fait une détection de l'ADN cible par diverses méthodes électrochimiques, y compris la voltamétrie cyclique, la voltampérométrie à onde carrée et la spectroscopie d'impédance. Cette stratégie a été réalisée d'abord avec la porphyrine Mn insérée puis généralisée à divers complexes métalliques pour une approche multidétection. Parallèlement, les nanomatériaux hybrides combinant les caractéristiques du graphène (haute conductivité et grande surface spécifique) et des porphyrines (propriétés physiques et chimiques et capacité de transfert d'électrons), tels que la tétraphénylporphyrine portant un et quatre groupes carboxyliques nommés H₂TPP-nCP (n = 1, 4) et la tétraphénylporphyrine incorporant du manganèse (III) (MnTPP-1CP) ont été synthétisés avec succès. L'interaction entre H₂TPP-nCP (n = 1, 4) et l'oxyde de graphène chimiquement réduit (CRGO) a été étudiée dans mon travail de thèse. Pour étudier les propriétés caractéristiques des nanomatériaux préparés, la microscopie électronique à balayage (MEB), la microscopie à force atomique (AFM), les spectres UV-visible, les spectres infrarouges à transformée de Fourier (FT-IR) et les spectres de photoélectrons X. Afin d'éliminer l'absorption non spécifique, la modification de l'électrode par le PEA a également été appliquée et obtenir une excellente application pour la détection de la cible d'ADNThe design and development of biosensors for direct detection of biomarkers in biological fluid sample is real challenge in research for their application in point of care system in diagnostic. My project is focus on the elaboration of a new platform for biological detaction composed of graphene which exhibits a high electroactive and specific surface suitable for grafting numerous biomoleculer with metalloporphyrins as a novel redox marker for following biological recognition process obtained in the case of DNA sensor. The concept will be to demonstrate that the metaloporphyrines where there redox potential could be controlled by the nature of metal ions could be applied in multidetection electrochemical biosensor platform. The association of metalloporphyrin with graphene will offer numerous advantages, as promoting electron transfer reaction and having a large surface for protein immobilization. The detection of target present will be performed following redox activity of the metalloporphyrins grafted on the surface. We have already synthesized various modified metalloporphyrins and characterizatized by usual spectrometry techniques such as NMR, UV and MS. The DNA biosensor has been constructed by the composite of graphene and metalloporphyrin and DNA probe as bioreceptor following covalent attachment approach and optimization of the biosensor construction for improving stability and reproducibility. And we have already done some detection of DNA Target by various electrochemical methods including cyclic voltammetry, square wave voltammetry and impedance spectroscopy. This strategy was performed firstly with on Mn inserted porphyrin and then generalized to various metal complex for multidetection approach. Meanwhile, the hybrid nanomaterials which combined the features of both graphene (high conductivity and large specific surface area) and porphyrins (physical and chemical properties and electron transfer ability), such as tetraphenylporphyrin bearing one and four carboxylic group named H₂TPP-nCP(n=1, 4) and tetraphenylporphyrin incorporating manganese (III) (MnTPP-1CP) were successfully synthesized. The interaction modes between H₂TPP-nCP(n=1, 4) and chemically reduced graphene oxide (CRGO) was studied in my thesis work. To investigate the characteristic properties of as-prepared nanomaterials, scanning electron microscopy (SEM), atomic force microscopy (AFM), UV-visible spectra, Fourier Transform infrared spectra (FT-IR), X-ray photoelectron spectra (XPS). In order to eliminate the non-specific absorption, the modification of the electrode by monolayer PEA was also applied and obtain excellent application for the detection of DNA target
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Lau, Kimberly Sui Fa. "Syntheses and evaluation of novel porpholactones for photonic applications /". Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/11609.
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Danso-Danquah, Richmond Edward. "Syntheses of polypyrrolic macrocycles". Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26240.
Testo completoAbstract (sommario):
Pentaphyrins are pentapyrrolic macrocycles containing five bridging methine groups between the five pyrrolic subunits. The syntheses of decamethylpentaphyrin 71, 2-ethoxycarbonyl-3,7,8,12,13,17,18,22,23-nonamethylpentaphyrin 74, 2-ethoxycarbonyl-3,7,8,22,23-pentamethyl-12,13,17,18-tetraethylpentaphyrin 75, 3,12-dimethoxycarbonylethyl-2,7,8,-13,17,18,22,23-octamethylpentaphyrins 29 and the zinc complexes of 71 and 74 are described.
The physical properties of the pentaphyrins show them to be aromatic like sapphyrins, porphyrins and corroles. This aromaticity is reflected in the large shielding of the NH protons and the deshielding of the methine protons in the nmr spectra and by their optical spectra, which exhibit Soret and visible bands similar to sapphyrins and porphyrins.Science, Faculty of
Chemistry, Department of
Graduate
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Steiger, George Edward. "Voltammetric investigation of rhenium and technetium tricarbonyl prophyrins". Thesis, Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/26947.
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Muller, Richard P. Goddard William A. "Development and implementation of ab initio methods for application to large molecules". Diss., Pasadena, Calif. : California Institute of Technology, 1994. http://resolver.caltech.edu/CaltechTHESIS:10292009-080702117.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--California Institute of Technology, 1994. UM #94-27,307.Advisor names found in the Acknowledgments pages of the thesis. Title from home page. Viewed 01/22/2010. Includes bibliographical references.
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Fowler, Christopher James. "The stability and coordination chemistry of metalloporphyrin isomers and self-assembled helices of 2,2'-biimidazoles /". Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004265.
Testo completo