08/11/20
Illumina library preparation kits use various bead types for different functions. While these beads often look similar, it is important to use the correct beads when called for because they have different properties and functions. All beads should be:
The tables below list bead types by function and provide additional information about each bead type.
DNA Purification
| Bead Name | Used in | Function | Additional information |
|---|---|---|---|
| AMPure XP beads |
Numerous Illumina library preparation kits |
Beads are used for DNA purification and/or size selection of DNA fragments based on the ratio of beads:sample. |
AMPure XP beads are purchased separately for use with Illumina library prep kits. Refer to the Equipment and Consumables section of the appropriate reference guide for the recommended Beckman Coulter catalog number. |
|
SPB (Sample Purification Beads) |
Numerous Illumina library preparation kits |
Beads are used for DNA purification and/or size selection of DNA fragments based on the ratio of beads:sample. |
Are functionally similar to AMPure XP beads. |
|
IPB (Illumina Purification Beads) |
Illumina DNA PCR-Free Prep, Tagmentation |
Beads are used for DNA purification and/or size selection of DNA fragments based on the ratio of beads:sample. | This bead is stored at room temperature. |
RNA Isolation and Purification
| Bead Name | Used in | Function | Additional information |
|---|---|---|---|
|
RPB (RNA Purification Beads) |
TruSeq Stranded mRNA | Beads isolate mRNA by capturing polyadenylated RNAs. | |
|
RPBX (RNA Purification Beads) |
Illumina Stranded mRNA Prep, Ligation | Beads isolate mRNA by capturing polyadenylated RNAs. | |
|
RRB (rRNA Removal Beads) |
TruSeq Stranded Total RNA | Beads remove rRNA by binding rRNA removal probes bound to rRNA. | |
| RNAClean XP Beads |
TruSeq Stranded Total RNA Illumina Stranded Total RNA Prep Ligation with Ribo-Zero Plus |
Beads are used to purify RNA through binding. In TruSeq Stranded Total RNA, these beads clean up the remaining RNA after rRNA is removed. | RNAClean XP beads are purchased separately from Beckman Coulter Genomics, Cat. No. A63987. |
Tagmentation
| Bead Name | Used in | Function | Additional information |
|---|---|---|---|
| BLT (Bead-Linked Transposomes) | Illumina DNA Prep, (M) Tagmentation (formerly Nextera DNA Flex) | Transposomes bound to beads fragment and tag (tagment) DNA input. | BLT is not interchangeable with eBLT, BLT-PF, or eBLTL. |
| eBLT (Enrichment Bead-Linked Transposomes) | Illumina DNA Prep with Enrichment (S) Tagmentation (formerly Nextera Flex for Enrichment) | Transposomes bound to beads fragment and tag (tagment) DNA input for subsequent enrichment. | eBLT is not interchangeable with BLT, BLT-PF, or eBLTL. |
| BLT-PF (Bead-Linked Transposomes PCR-Free) | Illumina DNA PCR-Free Prep, Tagmentation | Transposomes bound to beads fragment and tag (tagment) DNA input for Illumina DNA PCR-Free workflow. |
BLT-PF are not used in the TruSeq PCR Free library prep kit, where fragmentation is achieved with Covaris shearing. BLT-PF is not interchangeable with BLT, eBLT, or eBLTL. This bead is stored at -20C. |
| eBLTL (Bead-Linked Transposomes for Enrichment) | Illumina RNA Prep with Enrichment (L) Tagmentation | Transposomes bound to beads fragment and tag (tagment) cDNA for the Illumina RNA Prep with Enrichment Tagmentation workflow. |
eBLTL is not interchangeable with BLT, eBLT, or BLT-PF. |
Enrichment
| Bead Name | Used in | Function | Additional information |
|---|---|---|---|
| SMB (Streptavidin Magnetic Beads) | Numerous Illumina library preparation kits | Streptavidin bound to magnetic beads pulls down biotinylated capture probes. | Beads are not interchangeable with streptavidin beads from third-party vendors. |
Normalization
| Bead Name | Used in | Function | Additional information |
|---|---|---|---|
| LNB1 (Library Normalization Beads 1) | Numerous Illumina library preparation kits | Library normalization: a fixed volume of beads is added to each sample, beads bind and saturate with library fragments, excess library is washed away, and normalized library is eluted from the beads. | Eluted libraries are single-stranded DNA. |
| Equalizer Beads | AmpliSeq for Illumina library preparation kits | Library normalization: Equalizer Capture reagent is added to final libraries and washed Equalizer Beads are added to the sample. After library fragments are captured by the beads, the beads are washed, and normalized library is eluted from the beads. |
Eluted libraries are double-stranded DNA. AmpliSeq for Illumina Equalizer reagents are not compatible with TruSeq or Nextera libraries. |