Affymetrix
Oligonucleotides, usually 25-mers, are directly synthesized onto a glass wafer by a combination of semiconductor-based photolithography and solid-phase chemical synthesis technologies. Each array contains up to 6.5 million different oligos and each oligo is present in millions of copies. Since oligonucleotide probes are synthesized in known locations on the array, the hybridization patterns and signal intensities can be interpreted in terms of gene identity and relative expression levels by the Affymetrix GeneChip Operating Software (GCOS) and Command Console.

Array Type	Probe Design Region	No. of Probes	Measurement	Labeled Targets	Target Strand
3' Expression Array	-600bp 3'- UTR region	11 PM and MM pairs	Transcript level	cRNA	Anti-sense
Gene 1.0-ST	Whole transcript	-26 per transcript	Transcript level	Single Strand cDNA	Sense
Exon 1.0-ST	Whole transcript	-4 per exon	Transcript and Exon level, alternate splicing	Single Strand cDNA	Sense
Promoter Tiling Array	Promoter region	One probe every 35bp	TF binding, epigenetics, etc	Single or double strand DNA	Sense and/or antisense
Genome Tiling Array	Entire genome	One probe every 35bp	TF binding, epigenetics, Transcript mapping	Single or double strand DNA	Sense and/or antisense

Agilent
We have recently acquired the Agilent scanner and hybridization oven to expand the microarray services. Agilent arrays are 60-mers oligonucleotides synthesized on standard glass arrays using its patented SurePrint inkjet technology. Agilent provides arrays for gene expression, miRNA expression, Copy number, and ChIP-on-chip analysis. The current print density (244k features per slide) allows up to eight samples to be processed on a single slide. The new slides with 1 million features will be released late summer 2008. See for a complete list of available catalog arrays. Custom array design and manufacturing are also being provided through its.

NimbleGen
NimbleGen manufactures custom, high-density DNA arrays based on its proprietary Maskless Array Synthesizer (MAS) technology. The current array density is 385k up to 2.1 million features per slides. It offers arrays for gene expression, DNA methylation, chIP-on-chip, copy number, and sequence capture.  We are currently expanding our services to support NimbleGen DNA methylation and chIP-on-chip arrays. For a complete list of available arrays, please download its catalog.

Exiqon
Exiqon combines leading-edge scientific expertise in gene expression with its proprietary LNA™ technology. The most recent version of the miRCURY LNA™ microRNA Array contains more than 1200 capture probes covering all human, mouse and rat microRNA sequences annotated in miRBase 10.0. The array also covers all microRNAs of the viruses related to these three species.