How can I ensure efficient cDNA purification using SPRI beads?

To ensure that purification of cDNA using SPRI beads occurs efficiently throughout the protocol, use the magnetic device specifically recommended for each type of tube. If the protocol requires multiple purifications, do not use the same magnetic device for all steps.

Aliquot SPRI beads prior to use to avoid cross-contamination.
Bring SPRI-bead aliquots to room temperature prior to purification to facilitate binding of cDNA, and to decrease the possibility of contamination with air pollutants. Cold SPRI beads have a higher adsorption capacity for air contaminants such as pollen.
Mix SPRI beads with the sample by thorough pipetting. Do not vortex the beads once they are added to the samples. Vortexing can shear the DNA or break it away from the beads.
For kits requiring purification prior to PCR amplification, ensure complete removal of the reverse transcription reaction mixture from the bead-bound first-strand cDNA. Residual reverse transcription reaction mixture may interfere with downstream PCR amplification.
Ensure that SPRI beads are completely removed from the PCR-amplified double-stranded cDNA.
Properly dry the SPRI bead pellet after washing; overly dry pellets may affect the DNA elution efficiency. Click here to see how the ideal bead pellet looks.

General NGS-Seq