Summary: Turbo DNA Isolation From Gel
1. Run agarose gel in TAE buffer + 0.5 µg/ml EtBr. Run until bands are separated well.
2. Reduce buffer level in tank to below level of surface of gel.
3. Prepare filter/membrane sandwich as follows: Cut edges off of a piece of 3500 MW cut-off
dialysis tubing. Rinse with dH2O. Flatten on clean glass plate on bench top. Wet a Whatman GF/C
(glass fiber) filter with dH2O. Place on top of flattened dialysis membrane. Using forceps, lift
and drain filter/membrane sandwich. Cut into a rectangle somewhat wider than the DNA band to be
collected. Blot excess ddH2O with Kimwipes, but do not allow to dry.
4. Set up gel stand on bench: support clean glass plate with 2 pipette tip boxes over hand-held long
wavelength UV lamp.
5. Place gel in tray on gel stand. Make cut(s) in gel just in front of band using a scalpel.
6. Insert filter/membrane sandwich into cut(s) in gel. Trim a plastic ruler and use as a guide.
7. Electrophorese at 50 - 100 V for 5-20 min. For 1 kb band try 10 minutes at 50 V. Examine gel
with UV lamp. Look for bright band visible from back of filter/membrane sandwich.
· Set up spin columns during electrophoresis.
8. Remove filter/membrane sandwich and trim. Examine with hand-held long wavelength UV lamp.
9. Place trimmed filter/membrane sandwich in 0.5 ml tube with small hole in bottom (use needle).
10. Place 0.5 ml tube in labeled 1.5 ml tube. Spin 1 minute in microfuge at top speed.
11. Check for DNA with hand-held long wavelength UV lamp. Should have 25 - 50 µl of volume.
12. Add equal an volume of phenol:CHCl3. Vortex for 1 minute. Spin 1 minute in microfuge.