The ELISA (enzyme-linked immunosorbent assay) is a test which uses color change and antibodies to identify a substance. An indirect ELISA is one of three ELISA tests.
Urine varies in appearance, depending principally upon a body's level of hydration, as well as other factors. Normal urine is a transparent solution ranging from colorless to amber but is usually a pale yellow. In the urine of a healthy individual the color comes primarily from the presence of urobilin.
Normal and healthy urine is pale yellow in color. The human body produces urine as a way to rid itself of harmful toxins, which are broken down by the kidneys, getting them ready for disposal. It also contains sugars, water, and urobilins.