immunokromatograafilised

Immunochromatography, also known as lateral flow immunoassay, is a simple, rapid diagnostic technique that combines immunology with chromatographic separation. The principle rests on the movement of a liquid sample along a porous membrane by capillary action, carrying labeled antibodies that bind to specific antigens. When the target antigen is present, it forms a complex with the labeled antibody. This complex continues to migrate until it encounters a second line of immobilized antibodies on the strip, which capture the complexes and produce a visible signal, often a colored line. A control line further upstream indicates that the test has functioned correctly by capturing excess labeled antibody.

The advantages of immunochromatographic tests include speed, usually delivering results within minutes, minimal equipment requirements, and ease of use, making them suitable for point-of-care settings, fieldwork, and self-testing. Common applications encompass detection of infectious diseases such as HIV, influenza, hepatitis, and tuberculosis, as well as hormone levels, pregnancy testing, and environmental monitoring. Limitations involve lower sensitivity compared to laboratory-based assays such as ELISA; quantitative interpretation may be difficult, and false positives or negatives can occur due to cross-reactivity or inadequate sample volume.

Manufacturers produce a wide range of kits covering over a thousand analytes. Continuous improvements in nanomaterial labels, membrane technology, and sample preparation aim to enhance sensitivity, specificity, and multiplexing capabilities, broadening the scope of immunochromatography in clinical diagnostics and public health surveillance.