Illumina’s unique BeadArray technology is based on 3 micron silica beads that self assemble in microwells on either of two substrates: fiber optic bundles or planar silica slides. The beads have a uniform spacing of ~5.7 microns when randomly assembled on one of these two substrates. They are held in the microwells by both Van der Waals forces and hydrostatic interactions with the walls of the well.
Each bead is covered with hundreds of thousands of copies of a specific oligonucleotide that act as the capture sequences in one of Illumina’s assays. Outstanding characteristics of the BeadArray technology are 100% quality control of every single array and the high feature-redundancy (>20x average) providing high-confidence results.
The BeadArray technology is available in various multi-sample array formats: the 6x, 8x and 12x BeadChip formats.
