Division of Chemical Engineering and Materials Science, Ewha Womans University, Seoul, 03760, Republic of Korea.
Center for Supramolecular Optoelectronic Materials (CSOM) and Department of Materials Science and Engineering, Seoul National University, Seoul, 08826, Republic of Korea.
Top Curr Chem (Cham). 2022 Aug 10;380(5):35. doi: 10.1007/s41061-022-00389-3.
Cyclometalated Ir(III) complexes exhibit strong phosphorescence emission with lifetime of submicroseconds to several microseconds at room temperature. Their synthetic versatility enables broad control of physical properties, such as charge and lipophilicity, as well as emission colors. These favorable properties have motivated the use of Ir(III) complexes in luminescent bioimaging applications. This review examines the recent progress in the development of phosphorescent biolabels and sensors based on Ir(III) complexes. It begins with a brief introduction about the basic principles of the syntheses and photophysical processes of cyclometalated Ir(III) complexes. Focus is placed on illustrating the broad imaging utility of Ir(III) complexes. Phosphorescent labels illuminating intracellular organelles, including mitochondria, lysosomes, and cell membranes, are summarized. Ir(III) complexes capable of visualization of tumor spheroids and parasites are also introduced. Facile chemical modification of the cyclometalating ligands endows the Ir(III) complexes with strong sensing ability. Sensors of temperature, pH, CO, metal ions, anions, biosulfur species, reactive oxygen species, peptides, and viscosity have recently been added to the molecular imaging tools. This diverse utility demonstrates the potential of phosphorescent Ir(III) complexes toward bioimaging applications.
金属环铱(III)配合物在室温下具有亚微秒到数微秒的强磷光发射寿命。它们的合成多功能性能够广泛控制物理性质，如电荷和疏水性，以及发射颜色。这些有利的性质促使人们将铱(III)配合物应用于发光生物成像应用中。本综述考察了基于铱(III)配合物的磷光生物标记物和传感器的最新进展。它首先简要介绍了金属环铱(III)配合物的合成和光物理过程的基本原理。重点说明了铱(III)配合物的广泛成像用途。总结了用于照亮细胞内细胞器的磷光标记物，包括线粒体、溶酶体和细胞膜。还介绍了能够可视化肿瘤球体和寄生虫的铱(III)配合物。通过对金属环配体进行简单的化学修饰，赋予了铱(III)配合物很强的传感能力。最近又增加了温度、pH 值、CO、金属离子、阴离子、生物硫物种、活性氧物种、肽和粘度的传感器，作为分子成像工具。这种多样化的用途展示了磷光铱(III)配合物在生物成像应用中的潜力。
