Purify the Ligation Reaction Using AMPure XP Beads (E7420)
This is a point where you can safely stop the protocol and store the samples prior to proceeding to the next step in the protocol.
This caution sign signifies a step in the protocol that has two paths leading to the same end point but is dependent on a user variable, like the type of RNA input.
Protocol
Note: If you are selecting for larger size fragments (> 200 nt) follow the size selection recommendations in Appendix A on the manual.- To the ligation reaction (83.5 μl), add 16.5 μl nuclease-free water to bring the reaction volume to 100 μl.
- Add 100 μl (1.0X) resuspended AMPure XP beads and mix well on a vortex mixer or by pipetting up and down at least 10 times.
- Incubate for 5 minutes at room temperature.
- Quickly spin the tube in a microcentrifuge and place the tube on an appropriate magnetic rack to separate beads from the supernatant. After the solution is clear (about 5 minutes), discard the supernatant that contain unwanted fragments (Caution: do not discard the beads).
- Add 200 μl of freshly prepared 80% ethanol to the tube while in the magnetic rack. Incubate at room temperature for 30 seconds, and then carefully remove and discard the supernatant.
- Repeat Step 5 once for a total of 2 washing steps.
- Briefly spin the tube, and put the tube back in the magnetic rack.
- Completely remove the residual ethanol, and air dry beads for 10 minutes while the tube is on the magnetic rack with the lid open.
- Elute DNA target from the beads with 50 μl nuclease-free water. Mix well on a vortex mixer or by pipetting up and down, and put the tube in the
magnetic rack until the solution is clear. - Transfer the 50 μl supernatant to a clean PCR tube. Discard beads.
- To the 50 μl supernatant, add 50 μl (1.0X) of the resuspended AMPure XP beads and mix well on a vortex mixer or by pipetting up and down at least 10 times.
- Incubate for 5 minutes at room temperature.
- Quickly spin the tube in a microcentrifuge and place the tube on an appropriate magnetic rack to separate beads from the supernatant. After the solution is clear (about 5 minutes), discard the supernatant that contains unwanted fragments (Caution: do not discard the beads).
- Add 200 μl of freshly prepared 80% ethanol to the tube while in the magnetic rack. Incubate at room temperature for 30 seconds, and then carefully remove and discard the supernatant.
- Repeat Step 14 once for a total of 2 washing steps.
- Briefly spin the tube, and put the tube back in the magnetic rack.
- Completely remove the residual ethanol, and air dry beads for 10 minutes while the tube is on the magnetic rack with the lid open.
- Elute DNA target from the beads with 25 μl nuclease-free water. Mix well on a vortex mixer or by pipetting up and down, and put the tube in the magnetic rack until the solution is clear.
- Without disturbing the bead pellet, transfer 20 μl of the supernatant to a clean PCR tube and proceed to PCR enrichment.