Lateral-Flow Immunochromatographic Strip
Definition
A point-of-care format immunoassay in which a sample migrates along a nitrocellulose membrane past a labelled antibody zone and a capture antibody line. A visible band at the test line confirms the target antigen. Used for PSA detection in forensic triage because results appear within ten minutes without laboratory equipment.
- Target analyte
- PSA (prostate-specific antigen)
- Result time
- Under ten minutes
- Format
- Nitrocellulose membrane with labelled and capture antibodies
- Use context
- Forensic triage of sexual assault evidence
Common questions
Why is PSA testing used to screen for semen rather than confirm it outright?+
PSA is present at high concentration in semen but can also occur at lower levels in other body fluids, so a positive strip result directs the examiner toward confirmatory microscopy or DNA testing rather than standing alone as proof of semen.
How does a rapid PSA strip fit into evidence triage workflow?+
It lets an examiner quickly screen multiple swabs or stains at the scene or in the lab to prioritise which items are most likely to yield semen for full serological and DNA testing, saving laboratory time on low-probability items.
Related terms
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- Secretor
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