Cyanine7.5 carboxylic, a dye derivative of Cyanine 7.5 (Cy7.5) with carboxylic acid functional groups, is a near-infrared fluorescent dye extensively utilized in biomedical research areas, including biomarkers and cell imaging. Cyanine7.5 carboxylic can covalently bind to biological molecules (especially antibodies, proteins, etc.) to track their location and dynamic changes in biological samples.