CAS 25910-85-4: pinacryptol yellow

Pinakryptol Yellow is a carbocyanine dye. It is soluble in organic solvents and is used as a fluorescent probe for the detection of chloride in water. Pinakryptol Yellow has been shown to be sensitive to light exposure, with its fluorescence decreasing with increasing exposure. This compound absorbs ultraviolet radiation, which leads to excitation of the electrons and subsequent emission of visible light at a lower wavelength. The hydroxy group on the benzimidazole ring is responsible for this fluorescence. Pinakryptol Yellow also reacts with silver ions to form fluorescent silver complexes that can be detected using an electron microscope or by uv absorption spectroscopy. These reactions are dependent upon the presence of chloride ions, which are present in tap water and seawater but not pure water.