Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Acc Chem Res. 2021 May 4;54(9):2249-2260. doi: 10.1021/acs.accounts.1c00114. Epub 2021 Apr 23.
Porphyrin derivatives are ubiquitous in nature and have important biological roles, such as in light harvesting, oxygen transport, and catalysis. Owing to their intrinsic π-conjugated structure, porphyrin derivatives exhibit characteristic photophysical and electrochemical properties. In biological systems, porphyrin derivatives are associated with various protein molecules through noncovalent interactions. For example, hemoglobin, which is responsible for oxygen transport in most vertebrates, consists of four subunits of a globular protein with an iron porphyrin derivative prosthetic group. Furthermore, noncovalently arranged porphyrin derivatives are the fundamental chromophores in light-harvesting systems for photosynthesis in plants and algae. These biologically important roles originate from the functional versatility of porphyrin derivatives. Specifically, porphyrins are excellent host compounds, forming coordination complexes with various metal ions that adds functionality to the porphyrin unit, such as redox activity and additional ligand binding at the central metal ion. In addition, porphyrins are useful building blocks for functional supramolecular assemblies because of their flat and symmetrical molecular architectures, and their excellent photophysical properties are typically utilized for the fabrication of bioactive functional materials. In this Account, we summarize our endeavors over the past decade to develop functional materials based on porphyrin derivatives using bioinspired approaches. In the first section, we discuss several synthetic receptors that act as artificial allosteric host systems and can be used for the selective detection of various chemicals, such as cyanide, chloride, and amino acids. In the second section, we introduce multiporphyrin arrays as mimics of natural light-harvesting complexes. The active control of energy transfer processes by additional guest binding and the fabrication of organic photovoltaic devices using porphyrin derivatives are also introduced. In the third section, we introduce several types of porphyrin-based supramolecular assemblies. Through noncovalent interactions such as metal-ligand interaction, hydrogen bonding, and π-π interaction, porphyrin derivatives were constructed as supramolecular polymers with formation of fiber or toroidal assembly. In the last section, the application of porphyrin derivatives for biomedical nanodevice fabrication is introduced. Even though porphyrins were good candidates as photosensitizers for photodynamic therapy, they have limitations for biomedical application owing to aggregation in aqueous media. We suggested ionic dendrimer porphyrins and they showed excellent photodynamic therapy (PDT) efficacy.
卟啉衍生物在自然界中无处不在，具有重要的生物学功能，如在光捕获、氧气运输和催化等方面。由于其固有π共轭结构，卟啉衍生物表现出特征的光物理和电化学性质。在生物系统中，卟啉衍生物通过非共价相互作用与各种蛋白质分子相关联。例如，血红蛋白负责大多数脊椎动物的氧气运输，由四个球蛋白亚基组成，每个亚基都有一个铁卟啉衍生物的辅基。此外，非共价排列的卟啉衍生物是植物和藻类光合作用中光捕获系统的基本发色团。这些重要的生物学作用源于卟啉衍生物的功能多样性。具体来说，卟啉是优秀的主体化合物，与各种金属离子形成配位复合物，从而赋予卟啉单元更多的功能，如氧化还原活性和在中心金属离子处的额外配体结合。此外，由于其平面和对称的分子结构，卟啉是功能性超分子组装的有用构建块，并且其出色的光物理性质通常用于制造生物活性功能材料。在本综述中，我们总结了过去十年中使用基于仿生学的方法开发基于卟啉衍生物的功能材料的努力。在第一节中，我们讨论了几种作为人工别构宿主系统的合成受体，可用于选择性检测各种化学物质，如氰化物、氯和氨基酸。在第二节中，我们介绍了多卟啉阵列作为天然光捕获复合物的模拟物。通过额外客体结合的能量转移过程的主动控制以及使用卟啉衍生物制造有机光伏器件也被介绍。在第三节中，我们介绍了几种类型的基于卟啉的超分子组装体。通过金属-配体相互作用、氢键和π-π相互作用等非共价相互作用，卟啉衍生物被构建为形成纤维或环形组装体的超分子聚合物。在最后一节中，介绍了卟啉衍生物在生物医学纳米器件制造中的应用。尽管卟啉是光动力疗法（PDT）的良好光敏剂候选物，但由于在水介质中聚集，它们在生物医学应用方面存在局限性。我们提出了离子树状卟啉，它们表现出优异的光动力治疗（PDT）效果。
