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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Development of smart photosensitizers for targeted photodynamic therapy. / CUHK electronic theses & dissertations collection

January 2012 (has links)
本論文報導了幾個系列的新型鋅酞菁配合物以及氟硼二吡咯染料的合成與表徵。 這些精心設計的化合物可作為高效的和選擇性的光敏劑應用於靶向性光動力療法和細菌的光動力失活。 / 第一章概述了光動力療法,包括歷史發展、光物理和生物機制及其臨床應用現狀。 重點介紹了用於靶向性光動力療法的第三代光敏劑,其中包括基於靶向性配體、納米載體的光敏劑以及可激活的光敏劑。 另外,本章還簡單介紹了用於抗菌光動力療法的光敏劑。 / 第二章報導了一種新型的由細胞核定位的短肽共軛修飾的鋅酞菁配合物的合成與表徵。 此短肽分子的氨基酸序列為:Gly-Gly-Pro-Lys-Lys-Lys-Arg-Lys-Val。 我們研究了該化合物的光物理性質、聚集行為以及離體光動力活性,同時與其非肽共軛修飾的化合物進行了詳細的比較。 利用HT29人結腸腺癌細胞,研究發現此多肽共軛修飾的酞菁展示了較高的細胞吸收、更高的細胞內活性氧的產生效率和光毒性。 同時活體實驗證明此化合物增加了酞菁在裸鼠腫瘤的停留時間。 這些結果在本章中均進行了詳細的報導。 / 第三章敘述了另一種多肽共軛修飾的鋅酞菁化合物的製備和光物理性質。 這個多肽包含了一個環狀的氨基酸序列,即 Arg-Gly-Asp-D-Phe-Lys,此多肽被認為能以腫瘤相關的血管新生時的高表達的跨膜受體(如 α[subscript v]β₃ 整合素)為靶向。 利用 α[subscript v]β₃ 整合素高表達的 U87-MG 人惡性膠質瘤細胞,我們研究了這個化合物的細胞吸收、細胞內活性氧的產生、離體光動力活性以及亞細胞定位。 同時,用 α[subscript v]β₃ 整合素低表達的 MCF-7 人乳腺癌細胞作為對照。 / 通常,腫瘤細胞外的pH值比正常細胞組織的低,因此,我們合成一個由酸敏感的縮醛鍵連接的酞菁二聚體。 此二聚體會發生自身淬滅且對pH有響應。 通過電子吸收和熒光光譜, 我們詳細地研究了這個化合物在不同酸性條件下的光物理性質和斷開動力學。 由於酞菁環具有強的二聚化趨勢,這個二聚體能自身淬滅,因而呈現“失活狀態。 通過降低檸檬酸緩衝液的pH值,這個化合物的乙縮醛鍵能優先斷開,並且斷開的速率隨pH值的降低而增加。 兩個酞菁環的分開增強了熒光強度和單態氧的產生。 這個二聚光敏劑還能在 HT29 細胞內被激活,從而產生較強的細胞內熒光。 相比之下,由乙二醇鏈連接的類似物基本上沒有熒光發射。 同時,這個可斷開的二聚物對HT29細胞光毒性也比不可斷開的類似物高(半致死量:IC₅₀ = 0.35 vs. 0.59 μM)。 第四章對這些結果進行了詳細的報導。 / 在第五章中,我們報導了兩種以腫瘤靶向配體葉酸共軛修飾的二(苯乙烯基)-氟硼二吡咯衍生物的合成、光譜表徵以及光物理性質。 在這兩個化合物中,葉酸和二(苯乙烯基)-氟硼二吡咯是通過不同長度的乙二醇鏈連接的。 我們研究了這兩個化合物的鏈長對KB人鼻咽癌細胞和MCF-7細胞的吸收和離體光動力活性的影響。 前者能高表達葉酸受體,而後者作為低葉酸受體表達的一個對照。 與MCF-7細胞相比,兩個化合物都展示了對KB細胞較高的吸收和光毒性(半致死量:IC₅₀ = 0.062 vs. 2.56 μM 和0.177 vs. 0.995 μM)。 此外,具有較長鏈的化合物優先定位在溶酶體中,而較短鏈的那個化合物則較多停留在細胞的內質網。 / 第六章重點開發了一系列多胺以及不同長度的聚賴氨酸(包括2、4、8個賴氨酸)共軛修飾的鋅酞菁配合物,并用於抗菌光動力療法。 我們報導了它們的合成、光物理性質以及對甲氧西林青霉素敏感的格蘭陽性金黄色釀膿葡萄球菌和格蘭陰性綠膿桿菌的光動力抗菌活性。 其中,三-N-甲基化的酞菁顯示了特別高的效果,在濃度為16 nM時,能降低大於5 log10 的金黄色釀膿葡萄球菌。 / 第七章闡述了前面幾章的實驗部份。 論文的最後附上所有新化合物的核磁共振氫譜和碳譜。 / This thesis describes the synthesis and characterization of several series of novel zinc(II) phthalocyanines and boron dipyrromethenes (BODIPYs), which are carefully designed as efficient and selective photosensitizers for targeted photodynamic therapy (PDT) and photodynamic inactivation of bacteria. / Chapter 1 presents an overview of PDT, including its historical development, photophysial and biological mechanisms, and current research directions. Emphasis is placed on the third-generation photosensitizers for targeted PDT, including targeting ligand-based photosensitizers, nanoparticle-based photosensitizers, and activatable photosensitizers. A brief review of photosensitizers that can be used for antimicrobial PDT is also given. / Chapter 2 reports the synthesis and characterization of a novel zinc(II) phthalocyanine conjugated with a short peptide with a nuclear localization sequence, namely Gly-Gly-Pro-Lys-Lys-Lys-Arg-Lys-Val. The photophysical properties, aggregation behavior, and in vitro photodynamic activity of this compound have been investigated and compared with its non-peptide-conjugated analogue. It has been found that the peptide-conjugated phthalocyanine shows an enhanced cellular uptake, higher efficiency in generating intracellular reactive oxygen species (ROS), higher photocytotoxicity against HT29 human colorectal adenocarcinoma cells, and enhanced tumor-retention property in tumor-bearing nude mice. The results are reported in detail in this chapter. / Chapter 3 describes the preparation and photophysical properties of another analogue conjugated with a peptide containing the cyclic Arg-Gly-Asp-D-Phe-Lys sequence, which is known to target the upregulated transmembrane protein receptors such as α[subscript v]β₃ integrin during angiogenesis. The cellular uptake, intracellular ROS generation, in vitro photodynamic activity, and subcellular localization of this conjugate have been investigated against U87-MG human glioblastoma cells, which have a high expression of α[subscript v]β₃ integrin. MCF-7 human breast adenocarcinoma cells, which have a low expression of α[subscript v]β₃ integrin, have been used as a negative control. / On the base that the extracellular pH in tumors is generally lower than that in normal tissues, we have developed a pH-responsive self-quenched phthalocyanine dimer connected with an acid-sensitive ketal linker. The basic photophysical properties of this compound and its cleavage kinetics upon exposure to different acidic conditions have been extensively studied by electronic absorption and fluorescence spectroscopy. Owing to the strong dimerization tendency of the phthalocyanine ring, this dimer is self-quenched and in the "OFF" state. By lowering the pH (< 6.5) in citrate buffer solutions, the linker is preferentially cleaved, and the rate of cleavage increases as the pH decreases. The separation of the phthalocyanine moieties leads to enhancement in fluorescence intensity and singlet oxygen production. This dimeric photosensitizer can also be activated inside HT29 cells causing strong intracellular fluorescence. By contrast, the fluorescence is hardly observed for the non-cleavable ethylene glycol-linked analogue. The photocytotoxicity of the cleavable dimer is also higher than that of the non-cleavable counterpart (IC₅₀ = 0.35 vs. 0.59 μM). The results are reported in detail in Chapter 4. / In Chapter 5, we describe the synthesis, characterization, and photophysical properties of two distyryl BODIPY derivatives conjugated with a folic acid as a tumor-targeting ligand via an ethylene glycol spacer with different chain length. The effects of the chain length on the cellular uptake and in vitro photodynamic activities of these compounds have been examined against KB human nasopharyngeal epidermal carcinoma cells and MCF-7 cells. The former are known to have a high expression of folate receptors, while the latter have been used as a negative control. Both compounds show enhanced cellular uptake and higher photocytotoxicity toward KB cells when compared with MCF-7 cells (IC₅₀ = 0.062 vs. 2.56 μM and 0.177 vs. 0.995 μM). The conjugate with a longer spacer shows preferential localization in the lysosomes, while the analogue with a shorter linker accumulates in the endoplasmic reticulum of the cells. / Chapter 6 focuses on the development of a series of zinc(II) phthalocyanines substituted with a polyamine moiety or a polylysine chain containing 2, 4, or 8 lysine units for antimicrobial PDT. Their synthesis, photophysical properties, and photodynamic antimicrobial activities against Gram (+) methicillin-sensitive Staphylococcus aureus and Gram (-) Pseudomonas aeruginosa are reported. The tri-N-methylated phthalocyanine is particularly potent showing a more than 5 log₁₀ reduction of the Staphylococcus aureus at 16 nM. / Chapter 7 gives the experimental details for the work described in the preceding chapters. ¹H and ¹³C{¹H} NMR of all the new compounds are given in the Appendix. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Ke, Meirong. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 159-176). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.i / Abstract (in Chinese) --- p.v / Acknowledgment --- p.viii / Table of Contents --- p.xi / List of Figures --- p.xvi / List of Schemes --- p.xxiv / List of Tables --- p.xxv / Abbreviations --- p.xxvi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- General Introduction of Photodynamic Therapy --- p.1 / Chapter 1.2 --- Mechanisms of Photodynamic Therapy --- p.2 / Chapter 1.2.1 --- Photophysical Mechanisms --- p.2 / Chapter 1.2.2 --- Biological Mechanisms --- p.4 / Chapter 1.3 --- Clinical Status of Photodynamic Therapy --- p.5 / Chapter 1.4 --- Overview of Photosensitizers --- p.7 / Chapter 1.5 --- Targeted Photodynamic Therapy --- p.13 / Chapter 1.5.1 --- Targeting Ligand-Based Photosensitizers --- p.13 / Chapter 1.5.1.1 --- Synthetic Peptides --- p.13 / Chapter 1.5.1.2 --- Proteins --- p.16 / Chapter 1.5.1.3 --- Aptamers --- p.18 / Chapter 1.5.1.4 --- Folic acid --- p.19 / Chapter 1.5.1.5 --- Other Biological Ligands --- p.20 / Chapter 1.5.2 --- Nanoparticle-Based Photosensitizers --- p.20 / Chapter 1.5.2.1 --- Biodegradable Nanoparticle-Based Photosensitizers --- p.21 / Chapter 1.5.2.2 --- Non-Biodegradable Nanoparticle-Based Photosensitizers --- p.23 / Chapter 1.5.3 --- Activatable Photosensitizers --- p.25 / Chapter 1.5.3.1 --- Environment-Activated Photosensitizers --- p.26 / Chapter 1.5.3.2 --- Enzyme-Activated Photosensitizers --- p.27 / Chapter 1.5.3.3 --- Nucleic Acid-Activated Photosensitizers --- p.29 / Chapter 1.6 --- Antimicrobial Photodynamic Therapy --- p.32 / Chapter 1.6.1 --- General Introduction --- p.32 / Chapter 1.6.2 --- Photosensitizers for Antimicrobial Photodynamic Therapy --- p.34 / Chapter Chapter 2 --- A Phthalocyanine-Peptide Conjugate with High in vitro Photodynamic Activity and Enhanced in vivo Tumor-Retention Property --- p.36 / Chapter 2.1 --- Introduction --- p.36 / Chapter 2.2 --- Results and Discussion --- p.37 / Chapter 2.2.1 --- Molecular Design and Synthesis --- p.37 / Chapter 2.2.2 --- Electronic Absorption and Photophysical Properties --- p.42 / Chapter 2.2.3 --- In Vitro Photodynamic Activities --- p.44 / Chapter 2.2.4 --- In Vivo Studies --- p.50 / Chapter 2.3 --- Conclusion --- p.52 / Chapter Chapter 3 --- Synthesis, Characterization, and Photodynamic Activity of a cylic RGD-Conjugated Phthalocyanine --- p.53 / Chapter 3.1 --- Introduction --- p.53 / Chapter 3.2 --- Results and Discussion --- p.54 / Chapter 3.2.1 --- Molecular Design and Synthesis --- p.54 / Chapter 3.2.2 --- Electronic Absorption and Photophysical Properties --- p.57 / Chapter 3.2.3 --- In Vitro Photodynamic Activities --- p.59 / Chapter 3.3 --- Conclusion --- p.67 / Chapter Chapter 4 --- A pH-Responsive Fluorescent Probe and Photosensitizer Based on the Dimerization Property of Phthalocyanines --- p.69 / Chapter 4.1 --- Introduction --- p.69 / Chapter 4.2 --- Results and Discussion --- p.70 / Chapter 4.2.1 --- Synthesis and Characterization --- p.70 / Chapter 4.2.2 --- Electronic Absorption and Photophysical Properties --- p.74 / Chapter 4.2.3 --- In Vitro Studies --- p.80 / Chapter 4.3 --- Conclusion --- p.84 / Chapter Chapter 5 --- Synthesis, Characterization, and Photodynamic Activities of BODIPY-Folate Conjugates --- p.86 / Chapter 5.1 --- Introduction --- p.86 / Chapter 5.2 --- Results and Discussion --- p.87 / Chapter 5.2.1 --- Synthesis and Characterization --- p.87 / Chapter 5.2.2 --- Electronic Absorption and Photophysical Properties --- p.92 / Chapter 5.2.3 --- In Vitro Studies --- p.94 / Chapter 5.3 --- Conclusion --- p.100 / Chapter Chapter 6 --- Synthesis, Characterization, and Antimicrobial Photodynamic Activities of Cationic Phthalocyanines --- p.102 / Chapter 6.1 --- Introduction --- p.102 / Chapter 6.2 --- Results and Discussion --- p.103 / Chapter 6.2.1 --- Synthesis and Characterization --- p.103 / Chapter 6.2.2 --- Electronic Absorption and Photophysical Properties --- p.108 / Chapter 6.2.3 --- In Vitro Photodynamic Antimicrobial Activities --- p.112 / Chapter 6.3 --- Conclusion --- p.114 / Chapter Chapter 7 --- Experimental Section --- p.115 / Chapter 7.1 --- General --- p.115 / Chapter 7.2 --- Synthesis --- p.119 / Chapter 7.2.1 --- Synthesis for Chapter 2 --- p.119 / Chapter 7.2.2 --- Synthesis for Chapter 3 --- p.125 / Chapter 7.2.3 --- Synthesis for Chapter 4 --- p.128 / Chapter 7.2.4 --- Synthesis for Chapter 5 --- p.132 / Chapter 7.2.5 --- Synthesis for Chapter 6 --- p.138 / Chapter 7.3 --- pH-Response Properties of 4.6 and 4.7 in Citrate Buffer Solutions --- p.143 / Chapter 7.4 --- In Vitro Studies --- p.144 / Chapter 7.4.1 --- Cell Lines and Culture Conditions --- p.144 / Chapter 7.4.2 --- Photocytotoxicity Assay --- p.145 / Chapter 7.4.3 --- Photodynamic Antimicrobial Inactivatoin Studies --- p.147 / Chapter 7.4.4 --- Intracellular ROS Measurements --- p.148 / Chapter 7.4.5 --- Cellular Uptake (Determined by Extraction Method) --- p.149 / Chapter 7.4.6 --- Cellular Uptake (Determined by Confocal Microscopy) --- p.150 / Chapter 7.4.7 --- Cellular Uptake (Determined by Flow Cytometry) --- p.152 / Chapter 7.4.8 --- Fluorescence Microscopic Studies --- p.153 / Chapter 7.4.9 --- Subcellular Localization Studies --- p.153 / Chapter 7.4.10 --- pH-Dependent Intracellular Fluorescence Studies --- p.155 / Chapter 7.5 --- In Vivo Imaging and Ex Vivo Organ Biodistribution --- p.156 / Chapter Chapter 8 --- Conclusion and Outlook --- p.157 / References --- p.159 / Chapter Appendix --- NMR Spectra of New Compounds --- p.177
142

Nanocompósitos de ftalocianinas e xerogéis de pentóxido de vanádio (V) / Nanocomposites phthalocyanines and xerogels vanadium pentoxide (V)

Anaíssi, Fauze Jacó 13 June 1996 (has links)
Neste trabalho investigamos o comportamento estrutural da matriz de pentóxido de vanádio hidratado (V205.nH20) em função da presença de convidados moleculares intercalados. Para tanto utilizamos uma ftalocianina de cobre tetrassulfonada (CuPcTs), comercial da Aldrich. A intercalação desta no espaçamento interlamelar da matriz foi feita por dois procedimentos distintos. O primeiro consistiu em adicionar a solução de CuPcTS sobre a superficie da matriz previamente preparada, e deixar difundir em função da expansão lamelar provocada pelo solvente. O segundo método, que denominamos \'Ascenção Capilar\', consistiu em deixar a matriz em contato com a solução apenas por uma de suas bordas, controlando-se o tempo necessário para atingir a parte superior da matriz. Para caracterizar e diferenciar as amostras intercaladas ou não, utilizamos uma bateria de técnicas, como: difração de raios-X, espectroscopia eletrônica por transmissão e reflectância, espectroscopia vibracional raman ressonante e FTIR (por transmissão e reflectância), microscopia eletrônica de varredura (MEV), ressonância paramagnética eletrônica (RPE) e análise elementar de CHN. Com base nessas técnicas foi possível constatar que a intercalação aumenta o grau de cristalinidade das amostras, e que a ftalocianina se orienta paralelamente às lamelas. O método de Ascenção Capilar conduz a amostras com menor grau de deposição superficial. / The intercalation behavior of hydrated vanadium(V)-oxide xerogels (V2O5.nH2O) in the presence of a molecular guest, e.g. copper(II)-tetrasulphonated phtalocyanine, has heen investigated. Two distinct routes of intercalation have been employed. The conventional procedure consists in directly applying the phtalocyanine solution onto the freshly prepared films of the vanadium(V)-oxide host, and allowing enough time for interlamelar diffusion and drying. The alternative procedure employs an arrangement where the films are kept in a vertical position, in contact with the surface of the phtalocyanine solution, until the ascension by capillary diffusion is complete. The caracterization of the nanocomposites, and differentiation between the intercalated and adsorbed species was pursued with the use of a number of techniques, such as X-ray diffractometry, electronic and vibrational spectroscopy (absorption, and reflectance and resonance Raman), scanning electron microscopy, electronic paramagnetic resonance, and elemental analysis. The experimental results show that the intercalation proceeds with a parallel orientation of the phtalocyanine molecules within interlamelar planes, leading to an increse of the internal order or crystallinity. The samples prepared by vertical capillary diffusion exhibited a smaller degree of contamination with the adsorbed phtalocyanine at the film surface, in comparison to the conventional procedure.
143

Photodynamic activities and metal sensing behavior of boron dipyrromethenes and a silicon (IV) phthalocyanine. / CUHK electronic theses & dissertations collection

January 2010 (has links)
At the end of this thesis, the 1H and 13C {1H} NMR spectra of all the new compounds are listed in the Appendix. / Chapter 1 presents an overview of BODIPYs, including their general synthesis, properties, reactivities, and applications. The use of these compounds as photosensitizers for photodynamic therapy and fluorescent sensors for metal ions is highlighted. / Chapter 2 reports the synthesis, spectroscopic characterization, photophysical propreties, and in vitro photodynamic activities of a series of symmetrical distyryl BODIPYs substituted with one to five hydrophilic oligoethylene glycol monomethyl ether chain(s). In general, these compounds are essentially non-aggregated in DMF, resulting in a strong fluorescence emission and relatively high efficiency in generating singlet oxygen. Being formulated with 0.05% Tween 80, these compounds act as efficient photosensitizers. The compound which contains five triethylene glycol monomethyl ether chains exhibits the highest photocytotoxicity with an IC50 value as low as 7 nM toward HT29 human colorectal carcinoma cells. The high photodynamic activity of this compound can be attributed to its high efficiency in generating singlet oxygen, low aggregation tendency, and high cellular uptake. In addition, this compound also has a strong and selective affinity to the endoplasmic reticulum of the cells, causing cell death mainly through apoptosis. / Chapter 3 reports a related study on a series of unsymmetrical distyryl BODIPYs. These compounds possess three triethylene glycol monomethyl ether chains and another substituent at the other styryl group. The effects of this substituent on the photophysical properties, aggregation behavior, cellular uptake, and subcellular localization have been explored. Furthermore, their in vitro photodynamic activities have also been evaluated and compared with those of symmetrical analogues reported in Chapter 2. / Chapter 4 describes a novel ratiometric near-infrared fluorescent dye based on distyryl BODIPY with a 4-dimethylaminophenylethynyl group at the 2- and 6-positions. This compound exhibits a remarkable blue-shift in its absorption and fluorescence emission positions upon protonation with trifluoroacetic acid in organic solvents or HC1 in water in the presence of 0.05% Tween 80. These changes can be made reversible upon addition of a base. / Chapter 5 describes two monostyryl BODIPYs which contain two or four water-soluble amide chains as the metal chelators. The photophysical properties of these compounds and their spectral response to various metal ions have been investigated. The results show that the compound with two amide chains can detect Zn2+ ion in MeCN. They bind in a 1:1 stoichiometry with a binding constant of 2.2 x 104 M-1 . The fluorescence emission increases remarkably in intensity and shifts substantially to the blue from 620 to 572 nm due to the inhibition of the intramolecular charge transfer. The compound which contains four amide chains can detect Cd2+ ion with a high selectivity in phosphate buffered saline. / Chapter 6 reports the synthesis and spectral properties of a silicon(IV) phthalocyanine with two axial bis(2-picolyl)amine moieties which act as the binding sites for metal ions. The effects of various metal ions on its absorption and fluorescence spectra have been examined. The results indicate that this compound shows a relatively high sensitivity to Zn 2+ ion. Moreover, the proposed binding mode and the sensing mechanism are also discussed. / This thesis describes the synthesis and characterization of several series of functional boron dipyrromethenes (BODIPYs) and a silicon(IV) phthalocyanine. Their applications as efficient photosensitizers in photodynamic therapy and selective fluorescent sensors for metal ions are also reported herein. / He, Hui. / Adviser: Dennis Kee Pui Ng. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
144

Nanocompósitos de ftalocianinas e xerogéis de pentóxido de vanádio (V) / Nanocomposites phthalocyanines and xerogels vanadium pentoxide (V)

Fauze Jacó Anaíssi 13 June 1996 (has links)
Neste trabalho investigamos o comportamento estrutural da matriz de pentóxido de vanádio hidratado (V205.nH20) em função da presença de convidados moleculares intercalados. Para tanto utilizamos uma ftalocianina de cobre tetrassulfonada (CuPcTs), comercial da Aldrich. A intercalação desta no espaçamento interlamelar da matriz foi feita por dois procedimentos distintos. O primeiro consistiu em adicionar a solução de CuPcTS sobre a superficie da matriz previamente preparada, e deixar difundir em função da expansão lamelar provocada pelo solvente. O segundo método, que denominamos \'Ascenção Capilar\', consistiu em deixar a matriz em contato com a solução apenas por uma de suas bordas, controlando-se o tempo necessário para atingir a parte superior da matriz. Para caracterizar e diferenciar as amostras intercaladas ou não, utilizamos uma bateria de técnicas, como: difração de raios-X, espectroscopia eletrônica por transmissão e reflectância, espectroscopia vibracional raman ressonante e FTIR (por transmissão e reflectância), microscopia eletrônica de varredura (MEV), ressonância paramagnética eletrônica (RPE) e análise elementar de CHN. Com base nessas técnicas foi possível constatar que a intercalação aumenta o grau de cristalinidade das amostras, e que a ftalocianina se orienta paralelamente às lamelas. O método de Ascenção Capilar conduz a amostras com menor grau de deposição superficial. / The intercalation behavior of hydrated vanadium(V)-oxide xerogels (V2O5.nH2O) in the presence of a molecular guest, e.g. copper(II)-tetrasulphonated phtalocyanine, has heen investigated. Two distinct routes of intercalation have been employed. The conventional procedure consists in directly applying the phtalocyanine solution onto the freshly prepared films of the vanadium(V)-oxide host, and allowing enough time for interlamelar diffusion and drying. The alternative procedure employs an arrangement where the films are kept in a vertical position, in contact with the surface of the phtalocyanine solution, until the ascension by capillary diffusion is complete. The caracterization of the nanocomposites, and differentiation between the intercalated and adsorbed species was pursued with the use of a number of techniques, such as X-ray diffractometry, electronic and vibrational spectroscopy (absorption, and reflectance and resonance Raman), scanning electron microscopy, electronic paramagnetic resonance, and elemental analysis. The experimental results show that the intercalation proceeds with a parallel orientation of the phtalocyanine molecules within interlamelar planes, leading to an increse of the internal order or crystallinity. The samples prepared by vertical capillary diffusion exhibited a smaller degree of contamination with the adsorbed phtalocyanine at the film surface, in comparison to the conventional procedure.
145

In vitro and in vivo photodynamic activities for BAM-SiPc, an unsymmetrical bisamino silicon(IV) phthalocyanine.

January 2007 (has links)
Leung, Ching Hei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 101-110). / Abstracts in English and Chinese. / Acknowledgements --- p.i / 摘要(Abstract in Chinese) --- p.iii / Abstract --- p.v / List of Abbreviations --- p.vii / List of Figures and Tables --- p.ix / Table of Content --- p.xi / Chapter CHAPTER 1 --- Introduction / Chapter 1.1 --- History and development of photodynamic therapy --- p.1 / Chapter 1.2 --- Basic principle of photodynamic therapy: the beauty of the treatment --- p.3 / Chapter 1.3 --- "Photosensitizers: From discovery, synthesis to modifications" --- p.6 / Chapter 1.4 --- Enhancement of selective retention of PS in cancerous tissue --- p.10 / Chapter 1.5 --- Development of silicon (IV) phthalocyanine derivatives --- p.14 / Chapter 1.6 --- Death mechanisms in photodynamic therapy --- p.17 / Chapter 1.7 --- Objectives of the present study --- p.18 / Chapter CHAPTER 2 --- Materials and Methods / Chapter 2.1 --- Synthesis of BAM-SiPc --- p.20 / Chapter 2.2 --- Preparation of BAM-SiPc solution for photodynamic treatment --- p.20 / Chapter 2.3 --- Cell line and culture conditions --- p.21 / Chapter 2.4 --- Animal tumor model --- p.23 / Chapter 2.5 --- PDT laser source --- p.23 / Chapter 2.6 --- In vitro photodynamic activity assay --- p.23 / Chapter 2.6.1 --- Preparation of cells for photodynamic treatment / Chapter 2.6.2 --- In vitro photodynamic treatment / Chapter 2.6.3 --- Cell viability assay / Chapter 2.7 --- "Determination of reactive oxygen species production by 2',7'- dichlorofluorescein diacetate (DCFDA) assay" --- p.28 / Chapter 2.8 --- Analysis of cell cycle arrest --- p.28 / Chapter 2.9 --- Biodistribution of BAM-SiPc --- p.29 / Chapter 2.10 --- In vivo photodynamic treatment --- p.30 / Chapter 2.11 --- Assay for plasma enzyme activities --- p.30 / Chapter 2.12 --- Determination of cellular uptake of BAM-SiPc --- p.31 / Chapter 2.13 --- Metabolism of BAM-SiPc --- p.31 / Chapter 2.14 --- Histochemical staining --- p.32 / Chapter 2.14.1 --- Preparation of paraffin-embedded tissue section / Chapter 2.14.2 --- Haematoxylin and Eosin (H & E) staining / Chapter 2.14.3 --- Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay / Chapter 2.15 --- Conjugation of BAM-SiPc with LDL --- p.34 / Chapter 2.15.1 --- Analysis of the phototoxicity and cellular uptake of BAM- SiPc in the presence of LDL / Chapter 2.15.2 --- Gel filtration analysis of the mixture of LDL and BAM- SiPc / Chapter 2.16 --- Statistical analysis --- p.35 / Chapter CHAPTER 3 --- Results / Chapter 3.1 --- In vitro photodynamic activity assays --- p.36 / Chapter 3.2 --- Tissue distribution of BAM-SiPc in HepG2- bearing nude mice --- p.39 / Chapter 3.3 --- Anti-tumor activities of in vivo PDT with BAM-SiPc --- p.42 / Chapter 3.3.1 --- In vivo effect of PDT treatment with BAM-SiPc on HepG2 and HT29 tumor growth / Chapter 3.3.2 --- Dosage effect on anti-tumor activities by BAM-SiPc mediated PDT / Chapter 3.4 --- Analysis of intrinsic toxicity induced by BAM-SiPc mediated PDT --- p.48 / Chapter 3.4.1 --- H & E staining of liver sections of nude mice after in vivo PDT / Chapter 3.4.2 --- Plasma enzyme activity assays of PDT treated mice / Chapter 3.5 --- BAM-SiPc metabolism in in vitro culture cells and liver homogenate --- p.53 / Chapter 3.5.1 --- Cellular uptake of BAM-SiPc / Chapter 3.5.2 --- BAM-SiPc metabolism in cultured normal liver cells and cancer cells / Chapter 3.5.3 --- BAM-SiPc metabolism by mice liver homogenate / Chapter 3.6 --- Death mechanism induced by BAM-SiPc mediated PDT --- p.62 / Chapter 3.6.1 --- Events related to cell death induced by in vitro BAM-SiPc mediated PDT / Chapter 3.6.2 --- Death mechanism exerted by in vivo BAM-SiPc mediated PDT / Chapter 3.7 --- Effect on phototoxicity of BAM-SiPc in the presence of LDL --- p.70 / Chapter 3.7.1 --- Effect on phototoxicity of BAM-SiPc after mixing BAM- SiPc with LDL / Chapter 3.7.2 --- Gel filtration for analysis of the LDL-BAM-SiPc mixture / Chapter CHAPTER 4 --- Discussion / Chapter 4.1 --- Anti-cancer effect of BAM-SiPc on different cancer cell lines --- p.76 / Chapter 4.2 --- Tissue distribution of BAM-SiPc in HepG2 bearing nude mice --- p.77 / Chapter 4.3 --- In vivo effect of BAM-SiPc mediated PDT on HepG2 and HT29 tumor growth --- p.80 / Chapter 4.4 --- Analysis of the safety of using BAM-SiPc as a potential agent in PDT --- p.83 / Chapter 4.5 --- Metabolism of BAM-SiPc --- p.84 / Chapter 4.6 --- Mechanism of the apoptosis triggered by BAM-SiPc mediated PDT --- p.88 / Chapter 4.7 --- Death mechanism induced by in vivo PDT with BAM-SiPc --- p.93 / Chapter 4.8 --- Phototoxicity of BAM-SiPc in the presence of LDL --- p.94 / Chapter CHAPTER 5 --- Conclusion and Future perspective / Chapter 5.1 --- Conclusion --- p.97 / Chapter 5.2 --- Future perspective --- p.98 / References
146

Insights into Sulfonated Phthalocyanines; Insights into Anionic Tetraaryl Porphyrins; Irradiation of Cationic Metalloporphyrins Bound to DNA

Gill, Anila Fiaz 04 December 2006 (has links)
Sulfonated porphyrins and phthalocyanines have been under consideration as microbicides, compounds which, when used in a topical formulation, can prevent transmission of the human immunodeficiency virus. Our studies have been directed toward the characterization of members of these classes. For the sulfonated phthalocyanines, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry was helpful in determining the extent of sulfonation. We present the first report of spectroscopic characterization of a pentasulfonated phthalocyanine. Capillary electrophoresis data were sensitive to the concentration of the compounds (Chapter 1). Mass spectrometry was also very useful for establishing the extent of sulfonation in series of sulfonated porphyrins. Capillary electrophoresis was very useful in separating mixtures of these species. A study on sulfonation of a series of tetra(difluorophenyl)porphyrins showed that species with red-shifted Soret peaks were being formed. Data were consistent with an intramolecular sulfone bridge from the phenyl substituent to the porphyrin core. Sulfonation of the tetranaphthylporphyrins ring readily gave more than one sulfonic acid group per naphthyl side chain (Chapter 2). In cancer chemotherapy of solid tumors, it is desired to kill the tumor cells with minimal damage to the surrounding tissue. Brachytherapy seeds have been a considerable help in this regard for some tumors. In further developing approaches to selective tumor damage, we have evaluated a technique, Auger Electron Therapy (AET) in which one introduces a compound that is expected to bind to DNA, absorb the radiation, and then catalyze clustered DNA damage via release of a series of Auger electrons. We chose a series of metals (silver, indium, molybdenum, palladium, platinum, ruthenium, silver and zirconium) with appropriate energy levels to absorb an x-ray photon from the brachytherapy seed and used the tetracationic porphyrin 5,10,15,20-tetrakis(1-methylpyridinium-4-yl) porphyrin (TMPyP4) as a scaffold. The amount of clustered DNA damage was quantitated by a plasmid assay. Experiments evaluated the effect of buffer, concentration of glycerol, irradiation time, and concentration of the porphyrin. No metal studied gave significant double stranded (localized) DNA damage. Significant single stranded DNA damage was observed, however, in the order zirconium >> ruthenium > palladium > platinum > silver ~ indium (Chapter 3).
147

Synthesis And Characterization Of Electrochemically Polymerized Metal-free, Nickel And Zinc Containing Phthalocyanine Derivatives

Yavuz, Arzu 01 July 2009 (has links) (PDF)
In the first part of this study, 4-(2,5-di-2-thiophen-2-yl-pyrrol-1-yl)-phthalonitrile (SNS-PN) was synthesized by utilizing 1,4-di(2-thienyl)-1,4- butadione (SOOS) and 4-aminophthalonitrile via Knorr-Paal Reaction. Nuclear magnetic resonance (1H NMR and 13C NMR) and fourier transform infrared (FTIR) spectroscopies were utilized for the characterization of this compound. SNS-PN monomer was then electrochemically polymerized in acetonitrile/0.2 M LiClO4 solvent/electrolyte couple. Characterizations of the resulting polymer P(SNS-PN) were carried out by cyclic voltammetry (CV), UV&ndash / vis and FTIR spectroscopic techniques. Spectroelectrochemical studies revealed that P(SNS-PN) has an electronic band gap of 2.5 eV and exhibits electrochromic behaviour. The switching ability of polymer was also monitored. It was also found that P(SNS-PN) was fluorescent and its fluorescence intensity enhanced in the presence of cations. In the second part, novel tetrakis (4-(2,5-di-2-thiophen-2-yl-pyrrol-1-yl)) substituted metal-free (H2Pc-SNS), zinc (ZnPc-SNS) and nickel phthalocyanine (NiPc-SNS) complexes were synthesized and characterized by elemental analysis, FTIR and UV-Vis spectroscopies. The solution redox properties of these complexes were also studied by using CV and differential pulse voltammetry. All of the complexes showed two reversible reduction peaks having ligand-based character and one irreversible oxidation peak. Also, the electrochemical polymerization of these complexes was performed in dichloromethane/tetrabutylammonium perchlorate solvent/electrolyte couple. Resulting polymer films were characterized by UV&ndash / vis and FTIR spectroscopic techniques and their electrochemical behaviors were investigated utilizing CV. In-situ spectroelectrochemical investigations revealed that all the polymer films could be reversibly cycled and exhibit electrochromic behavior. Furthermore, the band gap of P(H2Pc-SNS), P(ZnPc-SNS) and P(NiPc-SNS) were calculated as 2.38 eV, 2.25 eV and 2.69 eV, respectively. Moreover, the fluorescence property of the P(ZnPc-SNS) was investigated in dimethyl sulfoxide and toluene.
148

Structure and Electronic Properties of Phthalocyanine Films on Metal and Semiconductor Substrates

Bidermane, Ieva 14 March 2014 (has links) (PDF)
The thesis presents fundamental studies of phthalocyanines (Pc), a group of organic macro-cycle molecules, similar to systems found in nature. The use of phthalocyanine molecular films in devices with a variety of possible technological applications has been the reason of the many studies during the last decades. Core and valence photoelectron spectroscopies (PES), X-ray absorption spectroscopy (XAS) and scanning tunneling microscopy (STM) techniques are used to study Pc molecules in gas phase and adsorbed on gold Au(111) and silicon Si(100)-2x1 substrates. Density function theory (DFT) is used to obtain further insights in the electronic structure of the phthalocyanines.We aim to obtain a deeper understanding of the molecule-molecule and molecule-substrate interactions, a fundamental requirement for improving devices based on organic materials. Gas phase PES experiments and DFT calculations performed on different Pcs show the influence of the metal atom on the valence band spectra, where FePc and H2Pc HOMO is formed from C2p states, whereas MnPc has mainly Mn3d character.PES and STM studies of H2Pc and LuPc2 on Au(111) show a formation of a monolayer for H2Pc and a bi-layer of LuPc2 at lower thicknesses. XAS studies show a parallel to surface orientation of both H2Pc and LuPc2 with a change in tilt angle of the molecules with increasing thickness.A comparison of LuPc2 adsorbed on pristine and passivated Si surfaces show a bulk-like LuPc2 character on passivated Si, whereas a surface induced difference in adsorption geometry is evidenced on pristine Si and two energetically different adsorption geometries are proposed.
149

Structure and Electronic Properties of Phthalocyanine Films on Metal and Semiconductor Substrates

Bidermane, Ieva 14 March 2014 (has links) (PDF)
The thesis presents fundamental studies of phthalocyanines (Pc), a group of organic macro-cycle molecules, similar to systems found in nature. The use of phthalocyanine molecular films in devices with a variety of possible technological applications has been the reason of the many studies during the last decades. Core and valence photoelectron spectroscopies (PES), X-ray absorption spectroscopy (XAS) and scanning tunneling microscopy (STM) techniques are used to study Pc molecules in gas phase and adsorbed on gold Au(111) and silicon Si(100)-2x1 substrates. Density function theory (DFT) is used to obtain further insights in the electronic structure of the phthalocyanines.We aim to obtain a deeper understanding of the molecule-molecule and molecule-substrate interactions, a fundamental requirement for improving devices based on organic materials. Gas phase PES experiments and DFT calculations performed on different Pcs show the influence of the metal atom on the valence band spectra, where FePc and H2Pc HOMO is formed from C2p states, whereas MnPc has mainly Mn3d character.PES and STM studies of H2Pc and LuPc2 on Au(111) show a formation of a monolayer for H2Pc and a bi-layer of LuPc2 at lower thicknesses. XAS studies show a parallel to surface orientation of both H2Pc and LuPc2 with a change in tilt angle of the molecules with increasing thickness.A comparison of LuPc2 adsorbed on pristine and passivated Si surfaces show a bulk-like LuPc2 character on passivated Si, whereas a surface induced difference in adsorption geometry is evidenced on pristine Si and two energetically different adsorption geometries are proposed.
150

Structure and Electronic Properties of Phthalocyanine Films on Metal and Semiconductor Substrates

Bidermane, Ieva January 2014 (has links)
The current thesis presents fundamental studies of phthalocyanines (Pcs), a group of organic macro-cycle molecules. The use of phthalocyanine molecular films in devices with a variety of possible technological applications has been the reason of the many studies dedicated to such molecules during the last decades. Core and valence photoelectron spectroscopies (PES), X-ray absorption spectroscopy (XAS) and scanning tunneling microscopy (STM) techniques are used to study phthalocyanine molecules in gas phase and adsorbed on gold (111) and silicon Si(100)-2x1 substrates. Density functional theory (DFT) is used to obtain further insights in the electronic structure of the phthalocyanines. The aim of our studies is to get a deeper understanding into the molecule-molecule and molecule-substrate interactions, a fundamental requirement for improving the devices based on such molecular materials. Gas phase PES and XAS studies and single molecule DFT calculations are performed on the valence band (VB) of iron phthalocyanine (FePc), manganese phthalocyanine (MnPc) and metal-free phthalocyanine (H2Pc). The VB simulations have shown how the metal atom of the Pc influences the inner valence states of the molecules. The HOMO of the H2Pc and FePc is formed by mostly C2p states, whereas the HOMO of MnPc has mainly Mn3d character. PES studies of H2Pc on Au(111) have revealed the influence of the surface on the adsorption of the monolayer. XAS studies indicate formation of ordered monolayer with the Pc ligands parallel to the surface and the change of the molecular tilt angle with increasing thicknesses. For LuPc2 adsorbed on Au(111), STM study demonstrates a formation of bilayer instead of a monolayer. A comparison between the results of LuPc2 adsorbed on pristine or passivated Si(100)-2x1 confirmes the different reactivities of these surfaces: LuPc2 retains many molecular-like characters, when adsorbed on the innert passivated Si. Instead, on the more reactive pristine Si surface, the spectroscopic results have indicated a more significant interaction, possible hybridization and charge redistribution between the molecules and the surface. Moreover, STM images show a modification of the geometrical shape of the molecules, which are proposed to adsorb in two different geometries on the pristine Si surface.

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