What is a Luminex Assay?

A Luminex assay is a type of immunoassay that precisely measures multiple analytes in one sample. The Luminex® xMAP® technology is a bead-based immunoassay that allows for multiplex detection of up to 100 analytes simultaneously. Color-coded microspheres, or beads, are internally dyed with different proportions of red and infrared fluorophores that correspond to a distinct spectral signature, or bead region. The quantification of multiple cytokines and other biomarkers in a sample provides critical information about biological processes and diseases.

Antibodies specific to a desired analyte are coupled to a unique bead region and are incubated with sample. After washing away unbound materials, samples are incubated with a mixture of biotinylated detection antibodies and a streptavidin-phycoerythrin (PE) reporter. Using a Luminex instrument, beads are excited by one laser to determine the bead region and corresponding assigned analyte. Another laser determines the magnitude of the PE-derived signal, which is proportional to the amount of analyte bound. Multiple readings are taken at each bead region, ensuring robust detection.