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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.iAbstract (in Chinese) --- p.vAcknowledgment --- p.viiiTable of Contents --- p.xiList of Figures --- p.xviList of Schemes --- p.xxivList of Tables --- p.xxvAbbreviations --- p.xxviChapter Chapter 1 --- Introduction --- p.1Chapter 1.1 --- General Introduction of Photodynamic Therapy --- p.1Chapter 1.2 --- Mechanisms of Photodynamic Therapy --- p.2Chapter 1.2.1 --- Photophysical Mechanisms --- p.2Chapter 1.2.2 --- Biological Mechanisms --- p.4Chapter 1.3 --- Clinical Status of Photodynamic Therapy --- p.5Chapter 1.4 --- Overview of Photosensitizers --- p.7Chapter 1.5 --- Targeted Photodynamic Therapy --- p.13Chapter 1.5.1 --- Targeting Ligand-Based Photosensitizers --- p.13Chapter 1.5.1.1 --- Synthetic Peptides --- p.13Chapter 1.5.1.2 --- Proteins --- p.16Chapter 1.5.1.3 --- Aptamers --- p.18Chapter 1.5.1.4 --- Folic acid --- p.19Chapter 1.5.1.5 --- Other Biological Ligands --- p.20Chapter 1.5.2 --- Nanoparticle-Based Photosensitizers --- p.20Chapter 1.5.2.1 --- Biodegradable Nanoparticle-Based Photosensitizers --- p.21Chapter 1.5.2.2 --- Non-Biodegradable Nanoparticle-Based Photosensitizers --- p.23Chapter 1.5.3 --- Activatable Photosensitizers --- p.25Chapter 1.5.3.1 --- Environment-Activated Photosensitizers --- p.26Chapter 1.5.3.2 --- Enzyme-Activated Photosensitizers --- p.27Chapter 1.5.3.3 --- Nucleic Acid-Activated Photosensitizers --- p.29Chapter 1.6 --- Antimicrobial Photodynamic Therapy --- p.32Chapter 1.6.1 --- General Introduction --- p.32Chapter 1.6.2 --- Photosensitizers for Antimicrobial Photodynamic Therapy --- p.34Chapter Chapter 2 --- A Phthalocyanine-Peptide Conjugate with High in vitro Photodynamic Activity and Enhanced in vivo Tumor-Retention Property --- p.36Chapter 2.1 --- Introduction --- p.36Chapter 2.2 --- Results and Discussion --- p.37Chapter 2.2.1 --- Molecular Design and Synthesis --- p.37Chapter 2.2.2 --- Electronic Absorption and Photophysical Properties --- p.42Chapter 2.2.3 --- In Vitro Photodynamic Activities --- p.44Chapter 2.2.4 --- In Vivo Studies --- p.50Chapter 2.3 --- Conclusion --- p.52Chapter Chapter 3 --- Synthesis, Characterization, and Photodynamic Activity of a cylic RGD-Conjugated Phthalocyanine --- p.53Chapter 3.1 --- Introduction --- p.53Chapter 3.2 --- Results and Discussion --- p.54Chapter 3.2.1 --- Molecular Design and Synthesis --- p.54Chapter 3.2.2 --- Electronic Absorption and Photophysical Properties --- p.57Chapter 3.2.3 --- In Vitro Photodynamic Activities --- p.59Chapter 3.3 --- Conclusion --- p.67Chapter Chapter 4 --- A pH-Responsive Fluorescent Probe and Photosensitizer Based on the Dimerization Property of Phthalocyanines --- p.69Chapter 4.1 --- Introduction --- p.69Chapter 4.2 --- Results and Discussion --- p.70Chapter 4.2.1 --- Synthesis and Characterization --- p.70Chapter 4.2.2 --- Electronic Absorption and Photophysical Properties --- p.74Chapter 4.2.3 --- In Vitro Studies --- p.80Chapter 4.3 --- Conclusion --- p.84Chapter Chapter 5 --- Synthesis, Characterization, and Photodynamic Activities of BODIPY-Folate Conjugates --- p.86Chapter 5.1 --- Introduction --- p.86Chapter 5.2 --- Results and Discussion --- p.87Chapter 5.2.1 --- Synthesis and Characterization --- p.87Chapter 5.2.2 --- Electronic Absorption and Photophysical Properties --- p.92Chapter 5.2.3 --- In Vitro Studies --- p.94Chapter 5.3 --- Conclusion --- p.100Chapter Chapter 6 --- Synthesis, Characterization, and Antimicrobial Photodynamic Activities of Cationic Phthalocyanines --- p.102Chapter 6.1 --- Introduction --- p.102Chapter 6.2 --- Results and Discussion --- p.103Chapter 6.2.1 --- Synthesis and Characterization --- p.103Chapter 6.2.2 --- Electronic Absorption and Photophysical Properties --- p.108Chapter 6.2.3 --- In Vitro Photodynamic Antimicrobial Activities --- p.112Chapter 6.3 --- Conclusion --- p.114Chapter Chapter 7 --- Experimental Section --- p.115Chapter 7.1 --- General --- p.115Chapter 7.2 --- Synthesis --- p.119Chapter 7.2.1 --- Synthesis for Chapter 2 --- p.119Chapter 7.2.2 --- Synthesis for Chapter 3 --- p.125Chapter 7.2.3 --- Synthesis for Chapter 4 --- p.128Chapter 7.2.4 --- Synthesis for Chapter 5 --- p.132Chapter 7.2.5 --- Synthesis for Chapter 6 --- p.138Chapter 7.3 --- pH-Response Properties of 4.6 and 4.7 in Citrate Buffer Solutions --- p.143Chapter 7.4 --- In Vitro Studies --- p.144Chapter 7.4.1 --- Cell Lines and Culture Conditions --- p.144Chapter 7.4.2 --- Photocytotoxicity Assay --- p.145Chapter 7.4.3 --- Photodynamic Antimicrobial Inactivatoin Studies --- p.147Chapter 7.4.4 --- Intracellular ROS Measurements --- p.148Chapter 7.4.5 --- Cellular Uptake (Determined by Extraction Method) --- p.149Chapter 7.4.6 --- Cellular Uptake (Determined by Confocal Microscopy) --- p.150Chapter 7.4.7 --- Cellular Uptake (Determined by Flow Cytometry) --- p.152Chapter 7.4.8 --- Fluorescence Microscopic Studies --- p.153Chapter 7.4.9 --- Subcellular Localization Studies --- p.153Chapter 7.4.10 --- pH-Dependent Intracellular Fluorescence Studies --- p.155Chapter 7.5 --- In Vivo Imaging and Ex Vivo Organ Biodistribution --- p.156Chapter Chapter 8 --- Conclusion and Outlook --- p.157References --- p.159Chapter Appendix --- NMR Spectra of New Compounds --- p.17