Nitrilotriacetic acid (NTA), C6H9NO6, is a chemical compound used as a chelating agent which forms coordination compounds with metal ions (chelates) such as Ca2+, Cu2+ or Fe3+. In 1999 about 20,000 tons of NTA were used in Europe.
The uses of NTA are similar to that of EDTA. However, in contrast to EDTA, NTA is easily biodegradable and is almost completely removed during wastewater treatment.
In biotechnology applications, NTA is combined with His-tags.