4-(7-Diethylaminocoumarin-3-yl)benzoyl cyanide (DACB-CN) serves as a multifunctional dye crucial for a wide array of applications. This chemical compound is utilized extensively in biological experiments to monitor and analyze various cellular components and activities. It aids in observing cell structures, tracking biomolecules, assessing cell functions, differentiating cell types, detecting biomolecules, examining tissue pathology, and studying microorganisms. Beyond its scientific research applications, DACB-CN is also employed in traditional industries like textile dyeing and in innovative sectors, including functional textile processing, food pigments, and dye-sensitized solar cells.