Fabrication of photo-encoded beads for bioanalysis

Encoding large libraries of biomolecules is important to the applications such as immunoassay, drug screening and so on. By now a number of encoding schemes have been proposed and developed. In this paper, a new encoding approach was proposed based on the photonic crystal beads and an apparatus was developed for the fabrication. Encoded beads, with diameters in the range between 0.2 mm and 3 mm, were prepared using polymer and pearl dye. Pearl dye is a kind of photonic crystal, the color of which is from the ordered nanostructure. Such a colorizing mechanism makes the color of pearl dye much stable to high temperature, UV irradiation or longtime storage comparing with the conventional dyes.