BeadXpress Reader FAQs

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  • Throughput depends on the level of multiplexing and whether you are running a single- or dual-color detection scanner. Typical throughputs are:


    Single-Color Detection

    Dual-Color Detection


    140 samples/hour

    120 samples/hour


    90 samples/hour

    68 samples/hour


    44 samples/hour

    30 samples/hour

    Multiplexing is achieved by pooling together beads with unique codes. Illumina offers standard products to enable users to develop anything from a single-plex to several hundred-plex reactions per sample in a single well.

    Carboxyl beads have a carboxylated surface, enabling development of protein-based assays. To achieve multiplexing, pool together different tubes of uniquely coded carboxyl beads after immobilizing with proteins of interest.

    For information on Illumina's regulatory, quality, and instrument safety certifications, including ISO certifications, go to the Regulatory and Quality Information page.

    Each uniquely coded VeraCode Universal Bead has a unique oligonucleotide capture sequence attached and can be used to design nucleic-acid based assays. For example, to develop a 3-plex reaction using a single-color detection assay, such as Allele Specific Primer Extension (ASPE), pool together six different tubes of unique VeraCode Universal Oligo Beads (one bead type per allele).

    The VeraCode technology is based on cylindrical glass microbeads measuring 240 μm in length × 28 μm in diameter. Illumina uses a proprietary technology to inscribe digital holographic elements within each bead. When a laser beam shines through the bead, the holographic elements diffract the light, creating a code image. Each different bead type contains a unique code that can be used to represent information such as the target of interest in multiplex assays. It can also be used to track critical information, including sample ID, laboratory ID, reagent lots, etc. The high-density codes (24 bit) offer a virtually unlimited number of unique bead types.

    The glass surface of the VeraCode beads make them ideal for a number of bioassays, including genotyping, gene expression, methylation, and protein-based assays. Solution-based assays, in conjunction with microarrays, can also be developed.