BeadArray Microarray Technology

Illumina's BeadArray microarray technology represents a fundamentally different approach to high-density arrays. 

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. When randomly assembled on one of these two substrates, the beads have a uniform spacing of ~5.7 microns. 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.

BeadArray microarray technology is utilized in Illumina's HiScan and iScan array scanners for a broad range of DNA and RNA analysis applications. BeadArray product density advancements have increased genomic coverage for whole-genome genotyping, resolution for cytogenetics and CNV detection, and sample throughput for gene expression, DNA methylation, and focused genotyping products.

The HiScan and iScan systems possess the advanced laser and optics components capable of handling even the highest density multisample arrays, producing high-quality data with rapid turnaround times.

The advanced Infinium HD assay delivers high data quality with an average call rate of 99.9%. These high sample call rates make downstream curation of data easy and decrease the likelihood of false positives and negatives.

Multi-sample array formats

BeadArray microarray technology is deployed on either of two multi-sample array formats for DNA or RNA analysis applications. With multi-sample BeadChip formats, uniform pits are etched into the surface of each substrate to a depth of approximately 3 microns prior to assembly. Beads are then randomly assembled and held in these microwells by Van der Waals forces and hydrostatic interactions with the walls of the well.


The Universal BeadChip format is used in Illumina's GoldenGate Genotyping and focused genotyping arrays.

The BeadChip array format is used in Illumina's Infinium Genotyping, DASL Gene Expression, and focused genotyping arrays.

Learn more about Illumina's microarrays »