Fluorescein dipropionate

Fluorescein is the most important xanthene dye widely used for labeling and sensing biomolecules. It has a high extinction coefficient and fluorescence quantum yield in aqueous solution, and its excitation wavelength is in the visible range. However, fluorescein also has some obvious deficiencies. Particularly its hydrophilic nature limits its application to the detection of enzymes, therefore fluorescein esters are a useful alternative. Fluorescein esters, such as fluorescein dipropionate, are nonfluorescent, but they can be cleaved by intracellular enzymes to yield fluorescent products, such as fluorescein. The rate of change in the fluorescence of the solution, due to the production of fluorescein, is measured and correlated with enzyme activity. Therefore, fluorescein esters could be used as fluorometric determination probes of enzymes. Fluorescein dipropionate could also be used as a building block or intermediate in synthesis of fluorescent probes.