AMPure PB / AMPure XP / SPB differences

[avo]

Does anyone know what the differences between the AMPure PacBio, AMPure XP or Illumina sample purification beads are? Different PEG concentrations,or if there no differences at all?

Thanks

[aerseq]

AMPure XP beads and AMPure "PB" beads

AMPure "PB" beads are pre-washed AMPure XP beads. According to the document below from Pacific Biosciences, the AMPure XP beads have a contaminant that elutes simultaneously with your nucleic acids and may interfere with polymerase binding, especially in low quantities of DNA. The supernatant of the AMPure XP beads is replaced after washing the beads.

http://www.pacb.com/samplenet/Guide_PacBio_Template_Preparation_and_Sequencing.pdf

See page 16 of 67 in the pdf cited above for the recommended washes. Does anyone know what the contaminant is? I haven't contacted Beckman Coulter regarding this.

[austinso]

Probably more important for PacBio, but azide is present (as a preservative), and that can affect polymerase activity.

[aerseq]

Does anyone use brands of SPRI beads (such as MagBio's HighPrep PCR beads) rather than Beckman Coulter's Agencourt AMPure XP beads?

[yeyue]

Does anyone use brands of SPRI beads (such as MagBio's HighPrep PCR beads) rather than Beckman Coulter's Agencourt AMPure XP beads?

so AMPure "PB" beads are the same with SPRI beads？

[nucacidhunter]

AMPure PB are specific formulation of AMPure XP for PacBio library clean ups and costs more than XP.