A microfluidic system for semicontinuous bead-based biosensing platforms

Conventional bead-based micro immunoassays do not guarantee high reliability because of the working principle for the trapping methods which cause inconsistency in trapping of cytometric beads. This paper presents a new bead-based micro immunoassay system for multiple or semicontinuous assays with high reliability and accuracy using hole-patterned structures and double-cladding optical fibers. Trapping test showed selective trapping of beads and consistency of the number of the trapped beads over repeated tests. Immunoassay using IL-6 showed that the cytometric beads were trapped in ordered fashion and provided a detection limit on the order of pg/ml.