The thesis examines for the first time the supercapacitive properties of three different nickel (II) phthalocyanine complexes, nickel (II) tetraamino phthalocyanine (NiTAPc), nickel (II) phthalocyanine and nickel (II) tetra tert-butylphthalocyanine as a) nanocomposites with multiwalled carbon nanotubes and as (b) an electropolymer supported on multiwalled carbon nanotube platform (MWCNT-polyNiTAPc). The supercapacitive properties of nickel (II) tetraaminophthalocyanine (NiTAPc)/multi-walled carbon nanotube (MWCNT) nanocomposite films have been found to possess a maximum specific capacitance of 981 F g-1 (200 mF cm-2), a maximum power density of 700 Wkg -1, a maximum specific energy of 134 Wh kg-1 and excellent stability of over 1500 chargedischarge continuous cycling. When compared to MWCNTs modified with unsubstituted nickel (II) phthalocyanine (MWCNT-NiPc) or nickel (II) tetra tert-butylphthalocyanine (MWCNT-tBuNiPc), MWCNT-NiTAPc exhibited superior supercapacitive behaviour, possibly due to the influence of nitrogen-containing groups on the phthalocyanine. The MWCNTpolyNiTAPc electrode had a maximum (112 mF cm-2) capacitance which was higher than that observed for MWCNT-polyNi(OH)TAPc (84.9 mFcm-2) but lower that of the MWCNT-NiTAPc (200 mF cm-2). Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Chemistry / unrestricted

Importance of clean, sustainable and renewable energy sources are increasing gradually because of either being environmental friendly or being alternative for fossil fuels. Hydrogen energy system will let the utilization of alternative energy sources. Fuel cells are the most suitable energy conversion devices while passing through the hydrogen economy. The cost of the fuel cell systems need to be reduced in order to achieve commercialization of these systems. One of the most important cost items is platinum which is used as catalyst both in anode and cathode sides of the proton exchange membrane (PEM) fuel cells. Not only is the cost of the platinum, but also the limited reservoir of the platinum is a handicap. Therefore, the utilization of the cheap replacements of platinum catalysts will accelerate the process of commercialization. Because of their highly conjugated structure and high chemical stability metalo phthalocyanines have been encouraging electrocatalytic activity for oxygen reduction. Therefore, electrocatalytic activity for oxygen reduction in fuel cells was studied with some metalo phthalocyanines and some positive effects have been observed. In this study, phthalocyanines of cobalt, iron and nickel were synthesized via phthalic anhydride-urea method and characterized by IR Spectrophotometry, X-Ray Diffractometry and Thermal Gravimetry (TGA). Catalyst materials were prepared by impregnation method such that they contain either 4% cobalt, 4% or 10% iron or 4% nickel phthalocyanines on carbon black (Vulcan XC72) structure. Impregnated catalysts were pyrolyzed at 600oC or 1000oC and cathode electrodes were prepared by these catalysts as well as unpyrolyzed ones by spraying technique. The impregnated catalysts were characterized by scanning electron microscopy (SEM) and pore structures were analyzed by surface area analyzer (by BET and BJH techniques). All of the anode electrodes were prepared by using 20% Pt containing commercial catalyst by the same technique applied for cathode electrodes. A membrane electrode assembly was also prepared by 20% Pt containing commercial catalyst on the cathode electrode. Performance characteristics of the manufactured membrane electrode assemblies were determined by means of a test station, built in Middle East Technical University Chemical Engineering Department, having a 5 cm2 test cell. The highest performance observed with the commercial membrane electrode assembly was 0.40W/cm2 at 0.5 V. Whereas, the power density obtained from the MEA manufactured at the laboratory having 0.4 mg Pt/cm2 loading both on the anode and cathode was 0.18 W/cm2 at 0.5 V. For the phthalocyanine cathodic MEAs, the highest power reached was 0.04W/cm2 which was obtained from the MEA having a loading of 0.28mg Co/cm2 prepared by using the CoPc/C catalyst pyrolyzed at 1000 oC.

Les anticorps (Ac) marqués à l'aide de phthalocyanines (Pc) ont un grand potentiel d'applications pour des essais d'immunofluorescence tout comme pour la thérapie photodynamique (PDT). La PDT est une forme relativement nouvelle de traitement du cancer ou d'autres maladies bénignes tel le psoriasis. Cette technique implique l'administration et l'activation par la lumière d'un photosensibilisateur localisé préférentiellement au niveau des cellules cancéreuses ou en croissance intense. La plupart des photosensibilisateurs utilisés pour la PDT sont de type porphyrine tels les Pcs. Dans cette étude, nous utilisons différentes phthalocyanines hautement solubles dans l'eau. Notre étude est basée sur l'utilisation d'anticorps monoclonaux comme vecteur des Pcs et comporte deux volets distincts. Tout d'abord l'utilisation des Pcs comme fluorochrome et finalement l'utilisation des complexes OKT3-AlPcS[indice inférieur 3]A[indice inférieur 1] dans l'amélioration de la PDT. Les Pcs sont liés de façon covalente aux Ac monoclonaux via une chaîne carboxy activée du Pc par la méthode de carbodiimide/N-hydroxysulfosuccinimide. Le complexe OKT3-AlPcS[indice inférieur 3]A[indice inférieur 1] lié à l'antigène de la surface cellulaire des cellules Jurkat CD3+ est visualisé par un trieur en cryométrie de flux (FACSCAN) et la phototoxicité in vitro est déterminée par un essai colorimétrique (test MTT). Nous avons donc produit un Ac de très bonne pureté et confirmé par cryométrie de flux la conservation de l'activité et de la spécificité de la liaison de l'Ac pour le récepteur après liaison covalente avec le Pc. Nous sommes ainsi les premiers à proposer l'utilisation des Pcs comme fluorochrome. Nous avons de plus vérifié la cytotoxicité médiée par le complexe qui s'est avérée non spécifique au clone cellulaire exprimant le récepteur CD3 reconnu par l'Ac. Nous proposons deux mécanismes de liaison du complexe OKT3-AlPcS[indice inférieur 3]A[indice inférieur 1] au niveau des cellules."--Résumé abrégé par UMI.

Phthalocyanines (Pcs) are highly conjugated, 18π-electron cyclic molecules composed of four isoindoline units that exhibit unique optical, electrical and chemical properties. While originally used as dyes and pigments, the use of Pcs in modern technology has increased dramatically due to improved understanding and processing capabilities. Work in this dissertation outlines a number of methods to prepare Pc-containing materials for use in various applications. Chapter 1 provides a brief review of methods used to prepare Pc-containing polymeric materials from both symmetric and asymmetric macrocycles. Discussion will focus on methods that incorporate symmetric Pcs as the focal point, with particular attention being paid to the influence of the peripheral substitution of the Pc on macromolecular structure and properties. Further discussion will focus on the utilization of asymmetric Pcs as auxiliary functionalities, such as at the terminus or as pendant groups, of larger macromolecular materials. Chapter 2 describes the preparation of linear Pc-containing polymers through ring-opening metathesis polymerization of a Pc monomer. Through proper selection of catalyst, well-defined polymers with Pcs as pendant groups were prepared. Due to the controlled nature of ROMP, polymers of varying architectures, composition, and size were synthesized. The effect of Pc metallation, polymer composition and architecture on the site-isolation of the chromophore was investigated in both solution and condensed-phase thin films. Chapter 3 reports on efforts to prepare linear polymers with companion functionalities for post-polymerization coupling of asymmetric Pcs. Polymers with pendant furan groups were prepared for coupling with asymmetric Pcs through Diels-Alder cycloaddition. Investigation indicated that while coupling was achievable, the presence of the Pc in the resultant polymer promoted undesired crosslinking when stored at ambient conditions in light. Attempts to mitigate this problem through alternation of functionality locations were attempted by placing the furan functionality on the Pc, but degradation of the furan occurred to quickly to perform coupling sufficiently. Chapter 4 discusses the preparation of Pc-containing networks through Diels-Alder cycloaddition of furan and maleimide containing tetrasubstituted Pcs. Following preparation of the various Pcs, network formation in various states was conducted including solution, molded thick films, and patterned assemblies. Chapter 5 summarizes the results presented in Chapters 2-4 and provides an outlook for some future directions based upon the work herein. In addition, some preliminary results of some of these directions will also be presented.

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department: Department of Biophysics and Physical Chemistry Candidate: Lenka Hrubá Supervisor: Assoc. Prof. Veronika Nováková, Ph.D. Title of Thesis: Optimization of methods for determination of singlet oxygen production and fluorescence emission of azaphthalocyanine derivatives Photodynamic therapy (PDT) with a singlet oxygen as an essential agent is believed to be an alternative way of cancer treatment or treatment of some cutaneous diseases. The principle of PDT is based on excitation of a photosensitizer by light absorption, followed by transfer of energy to tissue oxygen (3 O2) forming cytotoxic singlet oxygen (1 O2). The efficiency by which photosensitizer transforms absorbed energy to singlet oxygen is characterized by singlet oxygen quantum yields (ΦΔ). The aim of this thesis was to develop and optimize absolute method for determination of ΦΔ. In comparison to a relative method, no reference is needed in this case, which enables accurate results with lower error. Verification of the new method was performed in N,N- dimethylformamide with a zinc phthalocyanine as a model photosensitizer because of its well-known ΦΔ and with 1,3-diphenylisobenzofuran as a chemical quencher of 1 O2. Different sources of light for excitation...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department Department of Biophysics and Physical Chemistry Candidate Jiří Demuth Supervisor Assoc. Prof. Veronika Nováková, PhD. Title of Thesis Synthesis and photophysical study of hydrophilic tetrapyridoporphyrazines bearing charged substituents on the periphery Phthalocyanines are planar organic molecules, which have a metal cation coordinated in their centre. This work deals with their aza-analogues - tetra-3,4-pyridoporphyrazines (TPyPz). TPyPz can absorb light in red part spectrum and then produce singlet oxygen. Due to this ability, they may be used in photodynamic therapy (PDT) of cancer. PDT's mechanism is based on three components: photosensitizer, light and singlet oxygen. Photosensitizer transfers energy of absorbed light to oxygen making, thus, cytotoxic singlet oxygen. The goal of this thesis was to synthesize water soluble TPyPzs absorbing in red part of absorption spectrum. TPyPzs bearing different charged substituents will be compared within the series. The synthesis consisted of preparation of 2-chloro-5,6-dimethylpyridine-3,4-dicarbonitrile (1), which was the starting precursor for other reactions. Nucleophilic substitution of 1 was used for the introducing of various hydrophilic substituents. Prepared precursors...

A near-IR absorbing phthalocyanine containing alkylthio and alyklamino substituents along the periphery was determined to have optical properties that vary depending on surrounding solvent environment. Solvatochromic behavior of this novel chromophore has been characterized through UV-Vis absorbance and fluorescence spectroscopy. Conformational analysis using the B3LYP/6-31G* model indicates the lowest energy conformer with hydrogen bond like interactions between the sulfur lone pair and the hydrogen on the alkylamino substituent. TD-DFT analysis of the solvatochromic phthalocyanine and its parent molecule confirms the derivative exhibits tunable optical properties based on various solvent parameters. Chapter 1 reviews the energy crisis and the potential biological implications of near-IR absorbing phthalocyanines. In addition, a brief introduction of TD-DFT is given to further describe the computational analysis utilized herein. Chapter 2 describes the synthesis, spectroscopic studies, and computational analysis of a near-IR absorbing solvatochromic phthalocyanine derivative. Chapter 3 provides a summary of the work described in this thesis and provides future directions based on the completed research.

Hydrogen Sulfide (H2S) is an important biologically produced gasotransmitter along with carbon monoxide (CO) and nitric oxide (NO). Unlike CO and NO, the bioinorganic chemistry of H2S reactivity with biologically relevant metal centers remains underinvestigated. To address this gap, several model bio(in)organic complexes were used to understand the ligation and reaction chemistry of H2S, including phthalocyanine, protoporphyrin IX, tetraphenyl porphyrin, and a pyridine diimine zinc complex. In addition to being a reactive gasotransmitter, the hydrosulfide anion (HS–) has been found to be an important biological anion. Studies with readily available cobalt and zinc phthalocyanines in organic solution illustrated the importance of protonation state in the ligation and redox chemistry of H2S and highlighted the need for an organic-soluble source of HS–. To address this need, we developed a simple method to prepare tetrabutylammonium hydrosulfide (NBu4SH). Using NBu4SH, we expanded the knowledge of H2S reaction chemistry to encompass a significantly larger set of biologically relevant metals beyond iron using the protoporphyrin IX scaffold, revealing three principle reaction pathways: binding, no response, or reduction and binding. Iron in biology is of particular importance given its role in oxygen transport in hemoglobin. The swamp-dwelling bivalve L. Pectinata hemoglobin 1 (Hb1) transports H2S, via ligation to heme, to symbiotic bacteria. The stabilization of H2S in Hb1 is believed to be from one of the following: a protected pocket, hydrogen bonding with a proximal glutamate residue, or a complex combination of these or other factors. By using Collman's "Picket-Fence" porphyrin to isolate the protected pocket model, we determined that a protected pocket alone as insufficient to account for H2S stabilization on Hb1. This realization led to an examination of hydrogen bonding in the secondary coordination sphere of a zinc complex. Finally, we explored the role of HS– as a biologically relevant anion using a bis(ethynylaniline) supramolecular receptor. We determined that rather than covalently modifying the receptor molecule, HS– was bound in the pocket, similar to bacterial anion transport channel. This dissertation includes previously published co-authored material.

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