thumb|right|228px|Cultured embryonal carcinoma were stained with either DiI (red) or DiO (green). The image was captured by scanning confocal microscopy.
thumb|right|228px|Cultured embryonal carcinoma were stained with either DiI (red) or DiO (green). The image was captured by scanning confocal microscopy.
DiI, pronounced like Dye Aye, also known as DiIC18(3), is a fluorescent lipophilic cationic indocarbocyanine dye and indolium compound, which is usually made as a perchlorate salt. It is used for scientific staining purposes such as single molecule imaging, fate mapping, electrode marking and neuronal tracing (as DiI is retained in the lipid bilayers).
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).