Molecular Biology protocols, utilities and oddities
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Many labs run their DNA-PAGE gels with TBE, and use TBE as gel buffer, too.
I am, however, a good follower of Sajantila and Lukka, Int J Legal Med. 1993;105(6):355-9. Their protocol uses Tris-sulphate instead of TBE in the gel mix, and gave me much better resolution. Sequencing-long tris-sulphate (or even Tris-HCl!) gels can be run overnight with no loss of resolution. I used it to run overnight 1,5mm-thick, 40cm-long gels.
Here's my protocol, slightly adapted for big gels. You might go simpler with minigels.

1) Prepare stock solution for stacking and resolving:

H2O 77 ml

Acr/Bis 40%, 19:1 20 ml (8%)

Tris-Sulphate 1M pH 4.5 3 ml (30 mM)

TOTAL: 100 ml

(Best if degassed...)


2) Prepare plug:

Stock solution 20 ml

APS 10% (fresh) 140 µl

TEMED 10 µl

TOTAL 20 ml ca. (8%)


Pour plug (not all the 20 ml…), let polymerize.


3) set aside the stacking gel solution:

Stock solution: 10 ml

H2O: 9,4 ml

Tris-Sulphate 1M pH 4.5: 300 ul

TOTAL: 20 ml (4%)


4) Resolving gel:

Stock solution 70 ml

APS 10% (fresh) 490 µl

TEMED 35 µl

TOTAL 70 ml ca. (8%)


Pour, add a few drops of water-saturated n-butanol and let polymerize (vertically).


Thoroughly remove the butanol (do not let dry).


5) Stacking gel:

Stacking gel solution 20 ml (4%)

APS 10% (fresh) 140 µl

TEMED 10 µl

TOTAL 20 ml ca. (4%)


Pour, add the comb, and let polymerize.


Wash wells with TBE 0.5X.


Add samples in Ficoll loading dye:

Ficoll Loading dye, 6x:

TBE 0,5X 950 ul

Ficoll 400 125 mg (12.5%)

Sucrose 200 mg (20%)

Bromphenol blue a little

TOTAL 1 ml ca.

The original protocol by Sajantila and Lukka used:
 - a 12-cm 6%T, 1,6%C Polyacrylamide resolving gel
 - a 4-cm 3%T, 1,6%C Polyacrylamide stacking gel
 - Both gel solutions are prepared in 33 mM Trizma-Sulphate, pH 4.5, 7% glycerol.
 - Gel is run in TBE, pH 8.5 (2h50', 200V).
I decided to skip glycerol for my huge gels, and go for 30mM tris. My T/C ratio was different too (I used a 19:1 stock to prepare a 8%T, 0.4%C resolving gel).