Cyanine7.5 carboxylic acid chloride is a dye derivative of Cyanine 7.5 (Cy7.5) with carboxylic acid functional groups. Cy7.5 is a near-infrared fluorescent dye commonly used in biomedical research areas such as biomarkers and cell imaging. Cyanine7.5 carboxylic acid chloride can be covalently bound to some biological molecules (especially antibodies , proteins, etc.) to track their location and dynamic changes in biological samples.