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.
The normal color of urine can range from a translucent yellow to amber. It is a sterile liquid that is expelled from the body and is a product of cellular metabolism. The appearance of your urine can be affected by certain foods you eat, beverages you drink and diseases that you may be afflicted by. The yellow to amber color that normal urine has is due to a pigment called urochrome. When your urine is darker (amber), this usually is a sign you arenât getting enough fluids.