Encoded Porous Beads for Label-Free Multiplex Detection of Tumor Markers

Inverse-opaline photonic beads are used as the elements of a suspension array for label-free multiplex immunoassays. As in the case of tumor-marker detection, specific binding of tumor markers on the pore surfaces of the beads results in a shift in the diffraction-peak position, which can be used for quantitatively estimating the amount of bound tumor marker.