454 History of Luminescence 



Wochenschrift (7:428-430,1881) under the title, " Das Leuchten der 

 lebender und todten Substanzen." They served to show that not 

 only oils but also many other organic compounds are chemilumi- 

 nescent. 



The history of chemiluminescence in solution is indeed a late 

 development, mostly during the twentieth century, and a brief out- 

 line of these important discoveries follows because of their connec- 

 tion with light production by plants and animals. 



After Radziszewski's work, the next chemiluminescent compound *^ 

 to be discovered was pyrogallol, which is especially prone to lumi- 

 nesce in solution, as was first noticed by J. M, Eder (1887) and P. 

 Lenard and M. Wolf (1888) in developing a photographic plate with 

 pyrogallol developer. Many articles have subsequently appeared 

 from time to time describing the luminescence of photographic 

 plates. Later pyrogallol luminescence was studied in some detail by 

 Trautz and Schorigin (1904-1905) , who developed the well-known 

 luminescent mixture of pyrogallol, formaldehyde, potassium carbo- 

 nate, and hydrogen peroxide. Luminescence appears with many 

 organic compounds in presence of H2O2. 



Pyrogallol can hardly be called a biological compound although 

 some of its relatives play important roles in cell processes, especially 

 in the plant kingdom. With the turn of the century, in 1901, a most 

 important chemiluminescence of the substance, aesculin, the gluco- 

 side from horse-chestnut bark, was discovered by Raphael Dubois 

 (1849-1929) . His demonstration in 1887 of luciferin and luciferase, 

 the light-emitting constituents of luminous animals, had placed the 

 chemistry of bioluminescence on a firm foundation. Whenever a 

 solution of luciferin, a relatively simple oxidizable substance, and a 

 solution of the enzyme, luciferase, were mixed in the presence of 

 dissolved oxygen, light would appear. Dubois (1901) pointed out 

 that aesculin is a fluorescent substance and that it is only necessary 

 to mix it with alcoholic potash to obtain a bluish chemilumines- 

 cence, as bright as that from the mucous of the mollusc, Pholas 

 dactylus, containing luciferin and luciferase. However, the simi- 

 larity to bioluminescences was even closer. J. Ville and E. Derrien 

 discovered in 1913 that lophin could be oxidized with luminescence 

 in the presence of H^Oo and haemoglobin, the latter acting as a 

 catalyst, and Dubois in the same year found that aesculin would 

 also luminesce with H2O2 and haemoglobin. E. N. Harvey (1916) 

 noted the light emitted when pyrogallol is mixed with peroxidase 

 and H2O2. As a result of these experiments the fundamental light- 



*" B. Lachowiez (1882) reported the luminescence of paraphenanthrenchinon when 

 warmed in alcoholic KOH solution. 



