Pauly reaction

{{Short description|Chemical test for amino acid detection}}

The Pauly reaction is a chemical test used for detecting the presence of tyrosine or histidine in proteins. It is named after German chemist Hermann Pauly, who first described the reaction.{{Citation | last=Pauly | first=H | title=Über die Konstitution des Histidins. I. Mitteilung | journal=Z. Physiol. Chem. | volume=42 | issue=5–6 | year=1904 | pages=508–518 | doi=10.1515/bchm2.1904.42.5-6.508| url=https://zenodo.org/record/1448768 }} When proteins containing either tyrosine or histidine are reacted with diazotized sulfanilic acid under alkaline conditions, a red color is formed by a coupling reaction.{{cite book|author=Debajyoti Das|title=Biochemistry|url=https://books.google.com/books?id=QqXpWJHICUYC&pg=PA56|year=1980|publisher=Academic Publishers|isbn=978-93-80599-17-5|page=56}}{{cite book|author=John Henry Gaddum|title=Vasodilator Substances of the Tissues|url=https://books.google.com/books?id=czQ9AAAAIAAJ&pg=PA41|year=1986|publisher=CUP Archive|isbn=978-0-521-30860-1|page=41}}{{cite book|author=P. M. Swamy|title=Laboratory Manual on Biotechnology|url=https://books.google.com/books?id=_oFtJObOYTIC&pg=PA90|year=2008|publisher=Rastogi Publications|isbn=978-81-7133-918-1|page=90}}{{cite book|author=Joe Regenstein|title=Food Protein Chemistry: An Introduction for Food Scientists|url=https://books.google.com/books?id=OzL_W89s0qcC&pg=PA35|date=28 August 1984|publisher=Elsevier|isbn=978-0-323-15386-7|page=35}}