cycloreversion of DAE under light irradiation produces many exciting functional effects, such as changes in photophysical and photochemical properties, [12] changes in the shape or mechanical properties of the solid, [13] electrical conductivity, [7b,14] and the generation of reactive oxygen species (ROS). [15] This type of photochromic compound can be considered a stilbene derivative. At this time, the most widely known and systematically studied DAE derivative structure contains two aryl groups and a benzene ring (usually two identical or different thiophene units with low aromatic stabilization energy [16] ) and a five-membered ring of perfluorocyclopentene and cyclopentene units [17] where the ethene bridge is located, which significantly improve photochromism. [18] In essence, the DAE photoisomerization process is a reversible electrocyclic reaction of the central 6π-electron systems. [2] Under light irradiation, DAE can rapidly and reversibly transform between its open and closed forms, and that transformation is accompanied by a color change caused by a change in the π-conjugation distribution. [2] The important thing is that the colorless opened-and colored closed-ring isomers are both thermally stable; that is, cyclization and cycloreversion do not proceed spontaneously in the dark; they need to be driven by external light irradiation at specific wavelengths. [2,19] Compared with classic lightresponsive molecules such as azobenzene, [20] the light intensity required to drive the isomerization of DAE is relatively low. Moreover, even after multiple cycles, the photochromic performance does not show significant fatigue in either the solution or solid state. [2,18b,21] DAE research to this point can be roughly divided into three stages in chronological order: early exploration of DAE's molecular structure and theory, nearly two decades of purpose-oriented molecular structure modification research, and about ten years of research into practical applications of DAE in assembly systems. Research before about 2000 focused mainly on developing more abundant DAE-derivative structures and advancing the systematic understanding of DAE's physical and chemical properties and switching performance. To regulate its switching performance and give it new functionality, many strategies for modifying the ethene bridge and aryl groups of DAE have been proposed. [22] In the first two research stages, the mechanisms and structural modification of DAE isomerization were thoroughly and systematically explored, and countless important Diarylethene (DAE) photoswitch is a new and promising family of photochromic molecules and has shown superior performance as a smart trigger in stimulus-responsive materials. During the past few decades, the DAE family has achieved a leap from simple molecules to functional molecules and developed toward validity as a universal switching building block. In recent years, the introduction of DAE into an assembly system has been an attractive strategy that enables the photochromic behavior of the b...

owing to its large molar absorption coefficients, high emission quantum yields, satisfactory chemical stability, and high tunability of photophysical properties. [10,11] The conventional BODIPY core has good structural stability, in which BF 2 -chelated inhibits the rotation around the CN pyrrole bridging bonds, which enhances the structural rigidity and endows the system with fluorescence emission properties. [12] The BODIPY core has 8 covalently modified positions, which can be divided into pyrrole ring carbons, the meso-carbon, and the boron atom. [11,13,14] These abundant active sites provide lots of possibilities to expand the structure of BODIPY derivatives through functionalization and to tune their photophysical properties. [15] In the past few decades, the structural modification strategies of BODIPY units and the resulting effects have been systematically explored, [4,16] providing a solid research foundation for the current-stage design and construction of various functional BODIPY derivatives for different occasions. After decades of development, by virtue of the high molar extinction coefficient, longer wavelength absorbing, outstanding photosensitivity, satisfactory internal stability, better biocompatibility relative to inorganic dyes, high light-dark toxicity ratios, and preferable photothermal conversion efficiency (PCE), [4,[17][18][19] there has been considerable interest in exploring the application of BODIPY as photosensitizers (PSs) in the area of phototherapy, which involves the production of reactive The use of boron dipyrromethene (BODIPY) in biomedicine is reviewed. To open, its synthesis and regulatory strategies are summarized, and inspiring cutting-edge work in post-functionalization strategies is highlighted. A brief overview of assembly model of BODIPY is then provided: BODIPY is introduced as a promising building block for the formation of single-and multicomponent self-assembled systems, including nanostructures suitable for aqueous environments, thereby showing the great development potential of supramolecular assembly in biomedicine applications. The frontier progress of BODIPY in biomedical application is thereafter described, supported by examples of the frontiers of biomedical applications of BODIPY-containing smart materials: it mainly involves the application of materials based on BODIPY building blocks and their assemblies in fluorescence bioimaging, photoacoustic imaging, disease treatment including photodynamic therapy, photothermal therapy, and immunotherapy. Lastly, not only the current status of the BODIPY family in the biomedical field but also the challenges worth considering are summarized. At the same time, insights into the future development prospects of biomedically applicable BODIPY are provided.