1. Remove gel slice contain DNA fragment and place in 10 volumes of:

300 mM NaOAc, pH 7.0 300 ml 1 M NaOAC, pH 7.0

1 mM EDTA 2 ml 500 mM EDTA, pH 8.0

698 ml ddH₂O

2. Incubate at 22 ℃ for 30 min. Transfer gel slice to a fresh tube.

3. Place tube in a Dry Ice/Ethanol bath for 5 min.

4. Puncture the bottom of a 0.5 mL microcentrifuge tube with a needle. Place the gel slice into this tube. Place this tube inside a 1.5 mL microcentrifuge tube.

5. Centrifuge for 15 min.

6. Collect the Eluent from the 1.5 mL eppendorf tube. Extract and precipitate the DNA.