Medical Dictionary


adjective Kjel·dahl \ˈkel-ˌdäl\

Medical Definition of Kjeldahl

  1. :  of, relating to, or being a method for determining the amount of nitrogen (as in an organic substance) by digesting a sample with boiling concentrated sulfuric acid and other reagents, adding an excess of alkali, distilling, collecting the ammonia expelled, and determining the ammonia by titration <Kjeldahl analysis> <Kjeldahl apparatus>


\ˌkel-ˌdäl-ə-ˈzā-shən\play noun


\ˈkel-ˌdäl-ˌīz\play transitive verb




Biographical Note for kjeldahl



Johann Gustav Christoffer

(1849–1900), Danish chemist. Kjeldahl was the director of research at the chemical laboratory of the Carlsberg brewery. He introduced his method for the estimation of nitrogen in organic substances in 1883. In 1888 he constructed the Kjeldahl flask as an aid for simplifying the Kjeldahl method. The method is very important for agriculture, medicine, and drug manufacturing, and it is still used essentially as Kjeldahl developed it.

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