Figure 7 A self-assembled array of optically encoded microbeads into femtoliter-size wells on the ends of individual optical fibers. The identity of the bead is first determined followed by a measurement of the concentration of analyte attached to the bead by selective chemistries. (Courtesy of Illumina Inc.)

doi:10.1201/9780203910696-28

Chapter

Figure 7 A self-assembled array of optically encoded microbeads into femtoliter-size wells on the ends of individual optical fibers. The identity of the bead is first determined followed by a measurement of the concentration of analyte attached to the bead by selective chemistries. (Courtesy of Illumina Inc.)

Chapter

ABSTRACT

Much has been written about oligonucleotide, DNA or cDNA, and RNA microarrays. This technology was first commercialized by Affymetrix, Incyte, and Hyseq. It relies on surface micromachining techniques wherein the “layers” are successively photolithographically masked in light-directed oligonucleotide synthesis steps. For example, the Affymetrix technique works by shining light through a photolithographic mask onto a light-sensitive surface. The surface reactions are controlled so as to carry out the standard phosphoramidite oliognucleotide chemistry. Various cycles of protection and deprotection are required to build up a typical 20-mer oligo at specific sites.