Immunochromatographic assays

Definition

Immunochromatographic assays are rapid diagnostic tests that detect the presence of specific antigens or antibodies in a sample using a combination of immunochemical reactions and chromatography. These assays are commonly used in point-of-care testing due to their simplicity and quick results.

5 Must Know Facts For Your Next Test

1. Immunochromatographic assays often use colloidal gold nanoparticles as visible markers for antigen-antibody reactions.
2. They operate on the principle of lateral flow, where the sample moves along a test strip via capillary action.
3. These assays can provide qualitative or semi-quantitative results within minutes, making them suitable for rapid diagnosis.
4. Common applications include pregnancy tests, infectious disease detection, and drug screening.
5. Sensitivity and specificity of immunochromatographic assays can vary depending on the quality of antibodies used and the design of the assay.

Review Questions

• What principle do immunochromatographic assays operate on?
• Name two common applications of immunochromatographic assays.
• How do colloidal gold nanoparticles function in immunochromatographic assays?

Related terms

Enzyme Immunoassays (EIAs): Tests that use enzymes linked to antibodies or antigens to detect specific proteins.

ELISA:

A plate-based assay technique designed for detecting and quantifying soluble substances such as peptides, proteins, antibodies, and hormones.

Lateral Flow Test: A simple paper-based device intended to detect the presence (or absence) of a target analyte in liquid sample without the need for specialized equipment.