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.In biotechnology applications, NTA is combined with His-tags.
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