Spectrophotometric method for estimation of aliphatic primary amines in biological samples

Abstract

A method based on Rimini test for aliphatic amines was studied and developed for quantitative estimation of aliphatic primary amines. The method involves action of the amine with acetone to form schiff base which complexes with sodium nitroprusside to give violet colour. The absorption maximum in the visible range of the spectrum, for the reaction mixture was found to be 550 nm. The pH (8-11) and reaction time scan for the assay were optimized. A linear relation of concentration (0.2-3 mg/mL) of amine against absorbance at 550 nm was established. Interference due to other reaction components was negligible (±0.02 mg/mL) as compared to the sample in buffer. 1, 3-dimethyl butylamine was used as the model amine and the method was applied to other amines; it was observed that when electron-withdrawing substituents are present in the molecule the reaction is retarded, as the incubation time was longer. This method is useful for estimation of aliphatic primary amine in biological samples.

Valine and Phenylalanine as Precursors in the Biosynthesis of Alkamides in Acmella Radicans

“…Protein was quantified by Bradford's method, [29] using bovine serum albumin as standard. The isobutylamine product of valine decarboxylase was analyzed as described by Varma and Gaikwad [25].…”

“…However, such assays should be validated by establishing that CO 2 and amine production are in a 1:1 molar ratio because there are other reactions that can produce CO 2 . However, in order to confirm the presence of a valine and phenylalanine decarboxylase, we measured amine formation by UV absorption [25], instead of evolved CO 2 .…”