World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0002810615
Reproduction Date:

Title: Biuret  
Author: World Heritage Encyclopedia
Language: English
Subject: Urea, Non-protein nitrogen, Isocyanate, Carbamoyl aspartic acid, Ammeline
Publisher: World Heritage Encyclopedia


Skeletal formula of biuret
Ball-and-stick model of the biuret molecule
Space-filling model of the biuret molecule
Preferred IUPAC name
2-Imidodicarbonic diamide
Systematic IUPAC name
Other names
  • Allophanamide[1]
  • Carbamylurea[1]
  • Allophanic acid amide[1]
  • Allophanimidic acid[1]
  • N-Carbamoylaminomethanamide
  • Ureidoformamide[1]
  • Imidodicarbonic diamide
ChemSpider  Y
EC number 203-559-0
Jmol-3D images Image
Molar mass 103.08 g·mol−1
Appearance White crystals
Odor Odourless
131.3 J K−1 mol−1
146.1 J K−1 mol−1
−565.8–−561.6 kJ mol−1
−940.1–−935.9 kJ mol−1
GHS pictograms The exclamation-mark pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)
GHS signal word WARNING
H315, H319, H335
P261, P305+351+338
Irritant Xi
R-phrases R36/37/38
S-phrases S26, S36
Related compounds
Related compounds
urea, triuret, cyanuric acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
 N  (: Y/N?)

Biuret is a chemical compound with the chemical formula C2H5N3O2. It is also known as carbamylurea. It is the result of condensation of two molecules of urea and is a problematic impurity in urea-based fertilizers. This white solid is soluble in hot water. Biuret was first prepared and studied by Gustav Heinrich Wiedemann (1826 - 1899) for his doctoral dissertation, which was submitted in 1847. His findings were reported in several articles.[2][3][4][5]

The term "biuret" also describes a family of organic compounds with the functional group -(HN-CO-)2N-. Thus dimethyl biuret is CH3HN-CO-NR'-CO-NHCH3. A variety of organic derivatives are possible.


  • Preparation 1
  • Applications 2
    • Biuret test 2.1
  • Related compounds 3
  • References 4


The parent compound can be prepared by heating urea above the melting point at which temperature ammonia is expelled:[6]

2 CO(NH2)2 → H2N-CO-NH-CO-NH2 + NH3

Under related conditions, pyrolysis of urea affords trimerization of isocyanates. For example the trimer of 1,6-hexamethylene diisocyanate is also known as HDI-biuret.


Biuret is also used as a

  1. ^ a b c d e Scifinder, version 2007.1; Chemical Abstracts Service: Columbus, OH; RN 108-19-0 (accessed June 15, 2012)
  2. ^ Wiedemann, G. (1848). "Ueber ein neues Zersetzungsproduct des Harnstoffs" [On a new decomposition product of urea]. Annalen der Physik 150 (5): 67–84.  
  3. ^ Wiedemann, G. (1847). "Neues Zersetzungsproduct des Harnstoffs" [New decomposition product of urea]. Journal für praktische Chemie 42 (3–4): 255–256.  This notice reports that biuret reacts with alkaline copper sulfate to produce a red solution -- the so-called "Biuret test"
  4. ^ Wiedemann, G. (1848). "Ueber eine neue, aus dem Harnstoff entstehende Verbindung" [On a new compound arising from urea]. Journal für praktische Chemie 43 (5): 271–280. 
  5. ^ Wiedemann, G. (1848). "Biuret. Zersetzungsprodukt des Harnstoffs" [Biuret: decomposition product of urea]. Justus Liebig's Annalen der Chemie 68 (3): 323–326.  
  6. ^ a b Meessen, J. H.; Petersen, H. (2005), "Urea",  
  7. ^ Beef cattle feed, Encyclopædia Britannica Online
  8. ^ Kunkle, B.; Fletcher, J.; Mayo, D. (2013). "Florida Cow-Calf Management, 2nd Edition - Feeding the Cow Herd". IFAS Extension, University of Florida. Publication #AN117. 
  9. ^ a b Oltjen, R. R.; Williams, E. E.; Slyter, L. L.; Richardson, G. V. (1969). "Urea versus biuret in a roughage diet for steers".  
  10. ^ Fonnesbeck, P. V.; Kearl, L. C.; Harris, L. E. (1975). "Feed Grade Biuret as a Protein Replacement for Ruminants. A Review". Journal of Animal Science 40 (6): 1150–1184. 


Related compounds

The biuret test is a chemical test for proteins and polypeptides. It is based on the biuret reagent, a blue solution that turns violet upon contact with proteins, or any substance with peptide bonds. The test and reagent do not actually contain biuret; they are so named because both biuret and proteins have the same response to the test.

Biuret test

[10][9] but this characteristic also slows down its digestion and so decreases the risk of ammonia toxicity.[9] It is less favored than urea, due to its higher cost and lower digestibility[8]

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.