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.
No. Try this out:: Green urine is not normal (one of my definitions of normal is if I have had it's more likely to be normal and I have never had green urine :). B vitamins, esp. B1 and B2 can cause urine to become bright yellow.