Enzyme Immunoassay


Enzyme immunoassay is the most common drug-testing method. The Syva Company is the leader in this, with its EMIT test. EMIT can test for more than ten drugs, including marijuana, cocaine and amphetamines. A urine sample is broken into ten smaller samples, one for each drug. Then each is mixed with different antibodies. If drugs attach to the antibodies, the urine changes to a different colour depending on the drug. The colour changes tell laboratory people which drugs are in the urine.