Immunochromatographic Strip (Lateral-Flow Assay)
Definition
A single-use membrane device in which sample migrates by capillary action past a conjugate pad containing labelled antibody and a test line with capture antibody. A visible band at the test line indicates the presence of the target antigen. Results appear within 5 to 15 minutes without laboratory equipment.
- Result time
- 5 to 15 minutes
- Equipment needed
- None, field-deployable
- Readout
- Visible band at the test line
- Mechanism
- Capillary flow past conjugate and capture antibodies
Common questions
What does a missing control line indicate on a lateral-flow strip?+
An absent control line means the strip malfunctioned or the sample failed to migrate properly, so the result is invalid regardless of whether a test line appeared.
How does this differ from ELISA for species identification work?+
Lateral-flow strips trade sensitivity and quantitation for speed and portability, making them suited to rapid field screening, while ELISA remains the more sensitive, quantifiable laboratory-based confirmatory method.
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