BODIPY Fluorophores

Introduction

Boron dipyrromethene (BODIPY) fluorescent materials are novel fluorophores. They have high fluorescence quantum yield, high molar extinction coefficient, excellent photo-stability, Insensitive to environmental pH and so on. In addition, its chemical structure is easy to modify. Functionalization of the BODIPY core would form a series of derivatives，which can be used in the fields of environmental monitoring and biological sciences, etc. The specific functionalized BODIPY fluorophores are suitable for the selective analysis and detection of extremely small amounts of inorganic or organic ions and molecules. Fluorescence detection generally works through the following three mechanisms: Photoinduced Electron Transfer (PET), Intramolecular Charge Transfer (ICT) and Fluorescence Resonance Energy Transfer (FRET).

Fig.1 Three Fluorescence mechanism of BODIPY fluorescent sensor

Application

BODIPY fluorophores and its derivatives have been widely used in environmental monitoring, biological sciences and other field.

• Analysis and detection: BODIPY fluorophores by structurally modified have been used in ion probes and molecular probes. For example, a switch fluorescent probe (see fig.2) based on 6-hydroxyindole to detect Cu²⁺ has been reported ^[1] and the probe has good selectivity for other cations existing in organisms. In addition, a series of probes with selective recognition of Zn²⁺, Hg²⁺, Pb²⁺, CN^-, etc. have been designed and applied. In order to directly prove the role of NO in vivo, Zhang ^[2] prepared a new type of NO fluorescent probe. In the presence of NO, the fluorescence increased. It can effectively detect NO released by inducible nitric oxide synthase in tissue cells.

Fig.2 6-hydroxyindole switched fluorescent probe

• Diagnosis and Treatment of Tumor: Tumor is one of the diseases with the highest mortality rate in the world. Photodynamic therapy (PDT) is an emerging tumor therapy. At present, porphyrin derivatives are the most widely used PDT reagents in clinical application, but their photosensitivity and selectivity are not strong enough, so they are not ideal PDT test Because of its good photophysical properties, BODIPY fluorophores can be used as a kind of high efficiency Photosensitizers are used in photodynamic therapy as long as they are properly functionalized due to its large molar absorption coefficient and high chemical stability and light stability compared with other fluorophores.

Fig.3 Illustration of BODIPY act as photosensitizers ^[3]

References

1. Zhao, C. C.; et al. Boron dipyrromethene-derived Cu²⁺ sensing chemodosimeter for fast and selective detection. Org. Biomolecular. Chem. 2012, 10, 3104.
2. Zhang X.; et al. Development of a fluorescent probe for nitric oxide detection based on difluoroboradiaza-s-indacene fluorophore. Analytica Chimica Acta, 2003, 481(1): 101-108.
3. Feng, T.; et al. Application of fluoroboron fluoresceins (BODIPYS) and their derivatives in the synergistic diagnosis and treatment of tumor. Chin. J. Org. Chem. 2019, 39, 1891～1912.