Title:  Ninhydrin
CAS Registry Number:  485-47-2
CAS Name:  2,2-Dihydroxy-1
H-indene-1,3(2
H)-dione
Synonyms:  2,2-dihydroxy-1,3-indanedione;  1,2,3-indantrione monohydrate;  triketohydrinden hydrate
Molecular Formula:  C9H6O4
Molecular Weight:  178.14
Percent Composition:  C 60.68%, H 3.39%, O 35.93%
Literature References:  Prepn:  Ruhemann, 
J. Chem. Soc. 97, 1438 (1910); Teeters, Shriner, 
J. Am. Chem. Soc. 55, 3026 (1933); Wanag, Lode, 
Ber. 71, 1267 (1938).  Improved syntheses:  L. F. Fieser, 
Experiments in Organic Chemistry (Boston, 3rd ed., 1955) p 123; Becker, Russell, 
J. Org. Chem. 28, 1896 (1963).  Absorption spectrum:  Polonovski 
et al., Bull. Soc. Chim. [5] 
6, 1557 (1939).  Poisonous action on bacteria, mice, guinea pigs:  O. Loew, 
Biochem. Z. 69, 111 (1915).  Acute toxicity study:  J. C. Breton 
et al., C.R. Seances Soc. Biol. Ses Fil. 151, 719 (1957).  Monograph:  Henri Plagnol, 
Influence de la Structure des Composés Aminés dans leur Reaction avec la Ninhydrine (Bordeaux, 1962) 156 pp.  
Reviews:  J. C. Breton, 
Etudes Chimiques et Biologiques sur la Ninhydrine, Réactif des Aminoacides (Imprimerie E. Drouillard, Bordeaux, 1958) 285 pp; McCaldin, 
Chem. Rev. 60, 39 (1960); A. Schoenberg, E. Singer, 
Tetrahedron 34, 1285-1300 (1978).
 
Derivative Type:  Monohydrate 
Properties:  Pale yellow prisms from water or alcohol.  Reddens at 125°, swells at 139°, dec 241°.  Freely sol in water.  LD50 i.p. in mice:  78 mg/kg (Breton, 1957).
Toxicity data:  LD50 i.p. in mice:  78 mg/kg (Breton, 1957)
 
Use:  Reagent for the detection of free amino and carboxyl groups in proteins and peptides, yielding a blue color under the proper conditions.