A single-bead analysis on a disk-shaped microfluidic device using an antigen-immobilized bead.

A disk-shaped microfluidic device (lab-on-a-Disk) was developed to allow the evaluation of mental stress. As a standard sample, secretory immunoglobulin A (sIgA), which is a candidate marker of mental stress, was measured by a heterogeneous enzyme immunoassay (EIA) on the lab-on-a-Disk. Centrifugal force provided a microfluidic control on the lab-on-a-Disk.