Objective

This experiment aims to identify the presence of albumin in a urine sample.

Background

What is Albumin?

Albumin is a protein synthesized by the liver. It is a common component of blood , which is filtered by the kidneys.

The Role of Albumin

• It helps maintain the osmotic pressure inside the blood vessels, ensuring fluid balance.
• It serves as a transport protein for steroids, thyroid hormones, and fatty acids in the blood.

Understanding Albuminuria

Healthy kidneys usually allow very little albumin, about 250mg per day, to pass into the urine. However, kidney damage can lead to abnormal amounts of albumin in the urine, a condition known as albuminuria. If the albumin level is slightly above normal and remains so, it's referred to as microalbuminuria.

Causes of Albuminuria

• Diabetes-related kidney damage can lead to albuminuria.
• Kidney damage due to conditions such as high blood pressure, heart failure, lupus, and cirrhosis can also cause albuminuria.

The following tests can help detect albumin in urine:

• Heller’s Test – The presence of albumin causes a white ring to form.
• Sulphosalicylic Acid Test – Albumin causes coagulation, resulting in a cloudy white solution.

1. Heller’s Test

Materials Needed

• Concentrated nitric acid
• Urine sample
• Test tube
• Measuring cylinder
• Dropper
• Test tube holder

Method

• Measure 5ml of concentrated nitric acid using a measuring cylinder and pour it into a test tube.
• Add a few drops of the urine sample to the test tube using a dropper.
• Tilt the test tube and pour the urine sample along the inner side to create a layer over the nitric acid.
• Observe the changes in the test tube.

Results and Interpretation

If a white ring forms at the junction of the two layers, this indicates the presence of albumin in the urine sample.

2. Sulphosalicylic Acid Test

Materials Needed

• 30% Sulphosalicylic acid
• Urine sample
• Measuring cylinder
• Burner
• Test tube
• Test tube holder
• Dropper

Method

• Measure 2ml of the urine sample using a measuring cylinder and pour it into a test tube.
• Add a few drops of sulphosalicylic acid to the test tube using a dropper.
• The solution in the tube should turn white.
• Gently heat the tube using a burner while holding it securely with a test tube holder.
• Observe any changes in the tube.

Results and Interpretation

If the urine sample turns cloudy or white, this indicates the presence of albumin.

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