Download Heller’s-ring-test

TO STUDY THE PROPERTY OF DENATURATION OF
PROTEINS.
OBJECTIVE:
 To detect the properties of proteins in a
given solution.
 It is a general test for proteins.
PRINCIPLE:
 When proteins are treated with strong mineral acid
they are denatured.
REAGENTS:
 Nitric acid
 Original protein solution
PROCEDURE:
 Take 3ml of nitric acid in a test tube.
 Add 3ml of protein solution while inclining the test
tube so that proteins formed in layer over the acid.
INTERPRETATION:
 A white ring is formed at the junction of two solutions.
 This ring is made up of denatured protein.
 Yellow colour in the ring is due to nitro compound of
aromatic amino acids. It can be obtained by treating
the proteins with other acids like HCl and H2SO4.
Biomedical Importance:
 This is a general test for proteins and used to detect
the presence of proteins in urine.