DNA Sequencing Gel

A. STOCK SOLUTIONS:

10 X NNB:                Gel Fix:
162 g Tris base          10% Methanol
27.5 g Boric acid        10% Acetic Acid
9.3 g EDTA-Na2            2% Glycerol
870 ml Water

B. GEL:

   BOTTOM MIX:
------------------------------------------------------------
                           Small Gel    |   Big Gel (BRL)
------------------------------------------------------------
Urea                         4,8 g      |       9,6 g            8 M
Glycerol                    1,22 ml     |      2,44 ml          10 %
Acrylamide 50%-Bis 2,5%     1,60 ml     |      3,20 ml           8 %
NNB 10X                     2,50 ml     |      5,00 ml         2,5 X
Water                       1,75 ml     |      3,50 ml            -
                                        |
10% Persulfate                35 ul     |        70 ul
TEMED                          8 ul     |        16 ul
-------------------------------------------------------------
                 TOTAL        10 ml     |        20 ml
-------------------------------------------------------------
============================================================================
   TOP MIX:
------------------------------------------------------------
                           Small Gel    |   Big Gel (BRL)
------------------------------------------------------------
Urea                        19,2 g      |      28,8 g           8 M
Acrtlamide 50%-Bis 2,5%      6,4 ml     |       9,6 ml          8 %
NNB 10X                      2,0 ml     |       3,0 ml        0,5 %
Water                       16,8 ml     |      25,2 ml           -
                                        |
10% Persulfate               140 ul     |       210 ul
TEMED                         32 ul     |        48 ul
-------------------------------------------------------------
                 TOTAL        40 ml     |        60 ml
-------------------------------------------------------------

C. POURING:
 01. Take 6 ml of Top Mix in a 25 ml pipet 
 02. Take 6 ml of Bottom Mix in the same pipet
 03. Suck 1-2 bubles and let them pass through the solutions
 04. Apply in the sequence plate
 05. Complete with Top Mix
 06. Inclinate the plate (approx. 15o)
 07. Put the inverted comb (teeth upwards)
 08. Secure the top with black clamps
 09. Polymerize for at least 1 h
 10. Take the clamps out, put a wet piece of Whatman 3MM a wrap with
     Saran Wrap. Put the clamps back
 11. Let it stand one night (that makes the gradient even)

D. RUNNING:
 01. Make 1 liter of 1 x NNB
 02. Take the tapes (or clamps) out of the plate
 03. Take the comb out (with care!)
 04. Fill the single well with 1 x NNB
 05. Wash the outside of the glass plates with dd-water
 06. Put the comb in the well with the teeth downwards, softly touching
     the surface (DO NOT penetrate the gel!)
 07. Wash the wells with 1 x NNB using a syringe (to remove excess of urea)
 08. Heat samples at 85 oC for 3 min
 09. Put the samples immediatelly in a water-ice mixture
 10. Apply 3.5 ul of each sample and run at 30-45 watts for approx. 4h (TIL THE
     XYLENE CYANOL BLUE RUNS OUT OF THE GEL)
 11. Freeze the the reamining samples
 12. If you are going to make only one run go to step [13]. If not turn the power supply
     off, wash the wells again (see item 07) and apply the other half of the samples.
     Run for 2h at the same current (TILL THE BROMOPHENOL BLUE RUNS OUT OF THE GEL)
 13. Take the gel out, fix, dry and expose.