Heptamethine cyanine dyes (Cy7) have attracted much attention in the field of biological application due to their unique structure and attractive near infrared (NIR) photophysical properties. In this review, the influences of different modification sites on the absorption characteristics, photostability, Stokes shift, fluorescence characteristics, water solubility, and singlet oxygen generation efficiency of this class of dyes are summarized, and the application development of the corresponding dyes in the field of biological application is introduced, which will provide a reference for the optimization and improvement of heptamethine cyanine dyes in the future.

中文翻译：

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近红外七次甲基花青（Cy7）：从结构、性质到应用

七次甲基菁染料 (Cy7) 由于其独特的结构和吸引人的近红外 (NIR) 光物理特性而在生物应用领域备受关注。本文综述了不同修饰位点对此类染料的吸收特性、光稳定性、斯托克斯位移、荧光特性、水溶性和单线态氧生成效率的影响，以及相应染料在该领域的应用发展。介绍了生物应用方面的研究进展，为今后七次甲基菁染料的优化和改进提供参考。