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|Section2= |Section7= }} Luminol (C8H7N3O2) is a chemical that exhibits chemiluminescence, with a blue glow, when mixed with an appropriate oxidizing agent. Luminol is a white-to-pale-yellow crystalline solid that is soluble in most polar organic solvents, but insoluble in water. Forensic investigators use luminol to detect trace amounts of blood at crime scenes, as it reacts with the iron in haemoglobin. Biologists use it in cellular assays to detect copper, iron, and cyanides, as well as specific proteins by western blot. When luminol is sprayed evenly across an area, trace amounts of an activating oxidant make the luminol emit a blue glow that can be seen in a darkened room. The glow only lasts about 30 seconds, but investigators can document the effect with a long-exposure photograph. Crime scene investigators must apply it evenly to avoid misleading results, as blood traces appear more concentrated in areas that receive more spray. The intensity of the glow does not indicate the amount of blood or other activator present, but only shows the distribution of trace amounts of in the area. ==Synthesis== Luminol may be synthesized by a reverse-phosphorescence, two-step process. It begins from 3-nitrophthalic acid.〔(Synthesis of luminol )〕 First, hydrazine (N2H4) is heated with the 3-nitrophthalic acid in a high-boiling solvent such as triethylene glycol. An acyl substitution condensation reaction occurs, with loss of water, forming 3-nitrophthalhydrazide. Reduction of the nitro group to an amino group with sodium dithionite (Na2S2O4), via a transient hydroxylamine intermediate, produces luminol. Luminol was first synthesized in Germany in 1902,〔See: * Aloys Josef Schmitz, ("Ueber das Hydrazid der Trimesinsäure und der Hemimellithsäure" ) (On the hydrazide of trimesic acid (acid ) and of hemimellitic acid (acid )), Inaugural Dissertation, Heidelberg University, 1902; see pages 17 and 39-43. Schmitz calls luminol "1-amino-2,3-phtalsäurehydrazid". * Note: Gill states that luminol was prepared as early as 1853. See: Steven K. Gill (1983) "New developments in chemiluminescence research," ''Aldrichimica Acta'' 16 (3) : 59-61; see footnote 2 on page 60. Available at: (Aldrichimica Acta ). However, the sources Gill cites don't mention the preparation of luminol before 1902. Gill probably confused luminol with ''lophine'' (2,4,5-triphenyl-1''H'' -imidazole), which the sources he cites do mention. Lophine is also chemiluminescent, and was first prepared in 1844 by Auguste Laurent. (See: Auguste Laurent (1844) ("Sur un nouvel alcali organique, la lophine" ) (On a new organic alkali, lophine), ''Revue scientifique et industrielle'', 18: 272-278.) The chemiluminescence of lophine was first observed by: Radziszewski, Bronisław L. (1877) ("Untersuchungen über Hydrobenzamid, Amarin und Lophin" ) (Investigations of hydrobenzamide, amarine, and lophine), ''Berichte der Deutschen chemischen Gesellschaft zu Berlin'', 10 : 70-75. In 1853, Ludwig Teichmann developed a test for blood, but it did not rely on chemiluminescence. See: L Teichmann (1853) ("Ueber die Krystallisation der organischen Bestandtheile des Bluts" ) (On the crystallization of the organic components of blood), ''Zeitschrift für rationelle Medicin'', new series, 3 : 375-388.〕 but the compound was not named "luminol" until 1934.〔〔See also: Ernest H. Huntress, Lester N. Stanley, and Almon S. Parker (March 1934) "The oxidation of 3-aminophthalhydrazide ("luminol") as a lecture demonstration of chemiluminescence," ''Journal of Chemical Education'', 11 (3) : 142-145.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Luminol」の詳細全文を読む スポンサード リンク
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