Precipitate DNA

This step uses isopropanol (2-propanol), 100% and PM1 to precipitate the DNA.

• PM1
• Isopropanol (2-propanol), 100%
• Cap mats
• Foil adhesive seal
• Kimwipes
1. If the WGA plate was stored at -25°C to -15°C, thaw to room temperature.
2. Remove and discard the cap mat.
3. Prepare the following consumable:

Reagent

Storage

Instructions

PM1

2°C to 8°C

Bring to room temperature and invert to mix.

4. Preheat the Illumina Hybridization Oven to 48°C.
1. Add 100 μl PM1 to each well of the WGA plate.
2. Seal the WGA plate with the 96-well cap mat.
3. Vortex the plate at 1600 rpm for 1 minute.
4. Incubate on the preheated heat block for 5 minutes.
5. Pulse centrifuge at 280 × g for 1 minute.
6. Set the centrifuge at 4°C in preparation for the next centrifuge step.
7. Remove and discard the cap mat.
8. Add 300 μl 100% 2-propanol to each sample well.
9. Carefully seal using a foil adhesive seal.
10. Invert the plate 10 times to mix.
11. Incubate in a refrigerator set at 4°C for 30 minutes.
12. Centrifuge at 3000 × g at 4°C for 20 minutes.
13. Immediately remove the plate from the centrifuge.
• When centrifuging is complete, proceed immediately to avoid dislodging the blue pellets.
• If a delay occurs, repeat the 20 minute centrifuge.
14. Make sure that a blue pellet is present in the bottom of each sample well.
15. Remove and discard the foil adhesive seal.
16. Hold the plate over an absorbent pad and do as follows.
a. Quickly invert to decant the supernatant.
b. Drain liquid onto the absorbent pad, and then firmly tap the plate down on a dry area of the pad.
17. Keeping the plate inverted, firmly tap until all wells are free of liquid (~1 minute). Do not allow supernatant to pour in to other wells.
18. Place the uncovered, inverted plate on the tube rack for 1 hour at room temperature to air-dry the pellets.
19. Make sure that a blue pellet is still present in the bottom of each sample well.
20. Keeping the plate inverted, use a Kimwipe to remove any residual alcohol on the surface of the plate or draining from the wells of the plate.

Inverted WGA Plate

Do not overdry the pellets. Pellets that are overdried are difficult to resuspend and can lead to poor data quality.

SAFE STOPPING POINT

If you are stopping, seal the plate, and store at -25°C to -15°C for up to 24 hours.

If stopping for longer than 24 hours, store at -80°C.

[Optional] Unless you are stopping, you can set aside the WGA plate for up to 1 hour before proceeding.