LIFE SCIENCE

Detailed explanation-1: -Which colour is developed in ninhydrin test? The reaction of ninhydrin with an amino acid results in the creation of Ruhemann’s purple, a dark purple compound.

Detailed explanation-2: -Ninhydrin is used in many bioanalytical techniques particularly for amino acid analysis method. Ninhydrin reacts with the -amino group of primary amino acids producing ‘Ruhemann’s purple’.

Detailed explanation-3: -Ninhydrin is the most widely used chemical reagent for the detection of latent fingermarks on porous surfaces such as paper and cardboard. The compound reacts with the amino acid (eccrine) component of the fingerprint deposit to give a dark purple product known as Ruhemann’s purple (Figure 4).

Detailed explanation-4: -Updated On: 27-06-2022. Ninhydrin test is highly specific for primary amines. Proline being a secondary amine gives a yellow orange colour with Nlnhydrin whereas all other -amino acids give a blue purple colour with Ninhydrin.

Detailed explanation-5: -When excess of ninhydrin, which is originally yellow in color, reacts with a free -amino acid group, a purple colored dye known as Ruhemann’s purple is formed along with an aldehyde and liberation of CO2 gas(primary amines does not liberate CO2).