Electroelution of DNA from Agarose Gel

Electroelution of agarose fragments

Electroelution buffer

1 M Tris, pH 7.5 12.0 mls
0.5 M EDTA 0.24 mls
1 M NaCl 3.0 mls
qs to 600 mls dH2O

Acetate cushion
3 M NaAcetate pH 4.8 480 ul
0.1 % Bromphenol Blue 40 ul

1. Place gel slices in trough
2. Remove all air bubbles, then layer 80 ul of acetate cushion
3. Electroelute at: 120V for ~1Kb to 140V for >2.5Kb
for 40 min for ~1Kb to 60 min for >2.5Kb
4. Collect ~300 ul of salt cushion, add 3X volumes of 95% ethanol to precipitate
5. Remove gel slices
Clean wells
Run for 10 min longer
Clean wells again
Rinse thoroughtly to remove any extraneous DNA