A Multiplex Bead-Based Assay for Analyzing Cytokines in Human Tear Samples

Add human tear samples and an antibody-bead cocktail into a washed assay plate.

The antibodies are bound to color-coded magnetic beads, impregnated with varying proportions of fluorophores corresponding to distinct spectral signatures, facilitating multiple cytokine detection.

The tear cytokines bind to their corresponding bead-bound capture antibodies.

Using a magnetic plate washer, settle the antibody-bead complexes. Using buffer, remove the unbound biomolecules.

Add biotinylated detection antibodies that attach to the bound cytokines.

Pipette streptavidin-phycoerythrin conjugate, which binds to the biotinylated antibodies.

Using the plate washer, remove the unbound well contents. Resuspend the cytokine-bound complexes in sheath fluid.

During sample analysis, the fluidic system transports the bead complexes to the optics assembly.

The first laser activates the internal bead dyes, with the resulting signal identifying specific cytokines.

The second laser activates the reporter molecule bound to the bead complex, whose signal intensity represents the cytokine concentration, enabling simultaneous quantification of multiple cytokines.