Prozone effect
Definition
Paradoxical inhibition of the test band when haemoglobin concentration is extremely high, as excess antigen saturates all antibody binding sites and prevents the sandwich from forming. A positive result may be missed; dilution of the extract restores a visible band.
Related terms
- Anti-human haemoglobin antibody
- A monoclonal antibody raised against epitopes unique to human haemoglobin. Forms the detection and capture antibodies on the lateral-flow strip, conferring specificity...
- Control band (C line)
- A second line that captures excess labelled antibody regardless of whether the analyte is present. Its appearance confirms the assay ran correctly....
- Cross-reactivity
- A positive test result produced by a non-target species whose haemoglobin shares enough structural similarity to bind the anti-human antibody. For HemaTrace,...
- Lateral-flow immunochromatography
- A test format in which a liquid sample flows laterally along a membrane, encounters labelled detection antibodies, and is captured at specific...
- Test band (T line)
- The line on the lateral-flow card that appears when the anti-haemoglobin antibody captures haemoglobin-laden conjugate. Its presence constitutes a positive result.
Explained in
- RSID-Blood and ABAcard HemaTraceParadoxical inhibition of the test band when haemoglobin concentration is extremely high, as excess antigen saturates all antibody binding sites and prevents t...