Test of Urea in Urine (Principle and Methods) | Protein Metabolism

In this article we will discuss about the Principle and Methods of Test of Urea in Urine.

Principle of Test of Urea in Urine: 

Urea is split into ammonia and CO₂ by the enzyme urease present in plants at the opti­mum temperature and pH. Ammonium carbonate formed as a result of ammonia and carbon dioxide shows the alkali characteristic by the indicator.

Methods of Test of Urea in Urine:

1. 2 ml of urine in one test tube and 2 ml of water in another test tube.

2. A drop of phenol red is added to each of the test tubes.

3. 2 per cent Na₂CO₃ added drop by drop till the deep pink colour develops.

4. 1 or 2 drops of acetic acid added to each test tube till the colour is just yellow.

5. A pinch of soya bean powder added to each and the test tubes are rotated between the palms or the temperature is raised to 60°C, the optimum temperature for the enzyme urease.

6. The development of pink colour in the test tube containing urine indicates the presence of urea.