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Dische Test
The Dische test, or Dische reaction, is used to distinguish DNA from RNA. It was invented by Zacharias Dische Zacharias Dische (18 February 1895 – 17 January 1988) was an American biochemist of Ukrainian-Jewish origin. He worked as a biochemical researcher in Vienna before being forced by the Anschluß to become a refugee, first in France and then in th .... Method Dische's diphenylamine reagent consists of diphenylamine, glacial acetic acid, sulfuric acid, and ethanol. When heated with DNA, it turns blue in the presence of DNA. A more intense blue color indicates a greater concentration of DNA. Mechanism The acid converts deoxyribose to a molecule that binds with diphenylamine to form a blue substance. The reagent does not interact with RNA, so can be used to distinguish DNA from RNA. See also * Bial's test References {{reflist Analytical reagents Genetics techniques ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zacharias Dische
Zacharias Dische (18 February 1895 – 17 January 1988) was an American biochemist of Ukrainian-Jewish origin. He worked as a biochemical researcher in Vienna before being forced by the Anschluß to become a refugee, first in France and then in the US, where he joined the faculty of Columbia University in 1943. During his time in Marseilles he made a major discovery that is little known and usually attributed to others. Life Dische was born in Sambor, Austria-Hungary (present-day Ukraine). This account of Dische's life before he moved to the USA is based on the Memorial Book for the Victims of National Socialism at the University of Vienna in 1938. He enrolled at the Medical School of the University of Lemberg (Lviv) in 1913 and graduated in 1921, after service in the Austro-Hungarian Army, at the Medical School at the University of Vienna as Doctor of Medicine. From 1924 he researched on intermediary metabolism of blood cells at the University of Vienna, and developed simpl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphenylamine
Diphenylamine is an organic compound with the formula (C6H5)2NH. The compound is a derivative of aniline, consisting of an amine bound to two phenyl groups. The compound is a colorless solid, but commercial samples are often yellow due to oxidized impurities.P. F. Vogt, J. J. Gerulis, "Amines, Aromatic" in Ullmann’s Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. Diphenylamine dissolves well in many common organic solvents, and is moderately soluble in water. It is used mainly for its antioxidant properties. Diphenylamine is widely used as an industrial antioxidant, dye mordant and reagent and is also employed in agriculture as a fungicide and antihelmintic. Preparation and reactivity Diphenylamine is manufactured by the thermal deamination of aniline over oxide catalysts: : 2 C6H5NH2 → (C6H5)2NH + NH3 It is a weak base, with a ''K''b of 10−14. With strong acids, it forms salts. For example, treatment with sulfuric acid gives the bisulfate C6H5)2NH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bial's Test
Bial's test is a chemical test for the presence of pentoses. It is named after Manfred Bial, a German physician. The components include orcinol, hydrochloric acid, and ferric chloride. A pentose, if present, will be dehydrated to form furfural which then reacts with the orcinol to generate a colored substance. The solution will turn bluish and a precipitate may form. The solution shows two absorption bands, one in the red between Fraunhofer lines B and C and the other near the D line. An estimate of the relevant wavelengths can be made by referring to the Fraunhofer lines article. Composition Bial's reagent consists of 0.4 g orcinol, 200 ml of concentrated hydrochloric acid and 0.5 ml of a 10% solution of ferric chloride. Bial's test is used to distinguish pentoses from hexoses; this distinction is based on the color that develops in the presence of orcinol and iron (III) chloride. Furfural from pentoses gives a blue or green color. The related hydroxymethylfurfural from h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analytical Reagents
Generally speaking, analytic (from el, ἀναλυτικός, ''analytikos'') refers to the "having the ability to analyze" or "division into elements or principles". Analytic or analytical can also have the following meanings: Chemistry * Analytical chemistry, the analysis of material samples to learn their chemical composition and structure * Analytical technique, a method that is used to determine the concentration of a chemical compound or chemical element * Analytical concentration Mathematics * Abstract analytic number theory, the application of ideas and techniques from analytic number theory to other mathematical fields * Analytic combinatorics, a branch of combinatorics that describes combinatorial classes using generating functions * Analytic element method, a numerical method used to solve partial differential equations * Analytic expression or analytic solution, a mathematical expression using well-known operations that lend themselves readily to calculation * A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
