Lucifer yellow is a fluorescent dye used in cell biology.[1] The key property of Lucifer yellow is that it can be readily visualized in both living and fixed cells using a fluorescence microscope. Lucifer yellow was invented by Walter W. Stewart at the National Institutes of Health and patented in 1978.[2]
For common usage it is compounded with carbohydrazide (CH) and prepared as a lithium salt. The CH group allows it to be covalently linked to surrounding biomolecules during aldehyde fixation.[3]
Other cations such as ammonium or potassium can be used when lithium is undesirable, but the resulting salts are less soluble in water.
Lucifer yellow can also be compounded as a vinyl sulfone, with ethylenediamine, or with cadaverine.