Spectrophotometric determination of tryptophan by reaction with nitrous acid |
| |
Authors: | Verma K K Jain A Gasparic J |
| |
Affiliation: | Department of Chemistry, Rani Durgavati University, Jabalpur 482001, India. |
| |
Abstract: | The heterocyclic nucleus in tryptophan is oxidised by nitrous acid at elevated temperature to produce a phenolic intermediate which further reacts with nitrous acid to form a nitro compound that has a golden yellow colour in alkaline medium. The maximum absorbance is obtained at 400 nm with maximum molar absorptivity of 9.44 x 10(3) l.mole(-1). cm(-1). Derivatives of tryptophan such as indole-3-acetic acid, tryptamine and tryptophanamide, as well as indole, produce the same colour, but some others, e.g., 5-hydroxytryptamine and 5-hydroxyindole-3-acetic acid do not give the colour reaction. A plausible mechanism is proposed to explain this behaviour. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|