QIAquick purification of PCR products
Modified from Qiagen’s protocol with optimizations for low concentration PCR products
Works for products >100bp. Products as small as 50bp may work but concentrations will be reduced.
- Run 2uL of PCR product on a minigel to ensure the reaction worked.
- In a 1.5uL tube mix 5x the PCR product volumes of Buffer PB with 1uL pH indicator per 250uL Buffer. Mix and observe yellow color.
- Add the PCR product and mix by pipetting.
- If color changes from yellow to orange or purple, add 10uL 3M sodium acetate and mix.
- Place in a QIAquick column and provided 2mL collection tube.
- Centrifuge (max speed) 1 minute.
- Discard flow-through and place the column back in the collection tube.
- To wash, add 750uL Buffer PE to the column.
- Centrifuge 1 minute.
- Discard flow-through and place the column back in the collection tube.
- Centrifuge 1 minute to remove residual wash buffer.
- Discard collection tube and place column in labeled 1.5mL tube.
- To elute DNA, add 35uL Buffer EB to the center of the column membrane.
- Let column stand 2 minutes to maximize yield.
- Centrifuge 1 minute.
- Discard column. Purified PCR product is in the 1.5mL tube.
- Quantify on Nanodrop with EB as blank.
Recipes
3M Sodium Acetate
Combine in 15mL Falcon tube:
- 1.23g Sodium Acetate (m.w. = 82.03g/mol)
- 5mL ddH2O
Shake to mix. Store in refrigerator.