Lateral flow immunoassays are high performing, easy-to-use, and cost effective diagnostics widely used in rapid point of care testing. Lateral flow immunoassay systems are generally single-step assays, requiring only the addition of a sample. They consist of a sample pad or blood separator, conjugate release, nitrocellulose membrane, and an absorption pad. The sample flows from the sample pad/blood separator through to the conjugate release and contacts dried reagents, usually a tagged secondary antibody. The antibody and analyte then migrate to a capture zone of nitrocellulose membrane-immobilized antibody. Any unreacted tagged antibody flows past the capture zone to the absorption pad.
The visual evaluation allows for qualitative and semi-quantitative analysis, and using a LFD reader, the test strips can be analyzed quantitatively.