6-Chloro-3-indoxyl nonanoate is a fluorescent substrate that is used in the detection of beta-galactosidase activity. It has been used to detect the enzyme levels in various culture media and as a high quality, food testing, and environmental testing. The product is also used as a ligand for enzyme inhibition studies. 6-Chloro-3-indoxyl nonanoate has shown to be an excellent fluoroquinolone substrate for chemiluminescence assays.