Our objective is to detect the presence of albumin in urine.
Albumin is a protein produced by the liver and is mainly found in the blood. Its main functions are the ability to maintain intravascular oncotic pressure, meaning it keeps the fluid pressure stable within the blood vessels. It is also a carrier protein for steroids, fatty acids, and thyroid hormones in the blood.
A healthy kidney does not let albumin pass into the urine. A trace of protein which is less than 250 mg is found in normal urine daily. Under pathological conditions like albuminuria, level of albumin found in urine will be way above the normal level. Albuminuria indicates some damage to the kidney, as it is starting to pass some albumin into the urine. In kidney disturbance and in high blood pressure, albumin level in urine is significantly high.
We can test the presence of albumin in urine using Heller’s test and Sulphosalicylic acid test. Heller’s test causes the precipitation of albumin and forms a white ring in the solution. When heated or treated with sulphosalicylic acid, albumin undergoes coagulation and forms a white turbidity (cloudiness) in the solution.