Glossary
Lateral-flow immunoassay
The strip-format immunoassay used in most at-home and instant-result drug tests.
Last updated:Lateral-flow immunoassay strips use capillary action to draw urine across antibody-coated zones. A visible test line indicates the analyte is below the cutoff (negative); absence of the test line indicates a non-negative / presumptive positive that should be lab-confirmed.
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