Electrophoresis Buffers

Note: EDTA powder takes a long time to dissolve. It is better to prepare a 0.5M EDTA pH 8.0 stock solution and add liquid EDTA when preparing the buffers below.

Contents

1. TAE
2. TBE
3. TGS

1. TAE

Tris, Acetate, EDTA is used routinely for agarose electrophoresis of nucleic acids. The 1X working solution is 40 mM Tris-acetate/1 mM EDTA pH 8. We will make 5L of a 10x TAE concentrate and dilute to 1x prior to running a gel.

10x TAE: For 1 L

1. Dissolve 48.4 g Tris base in around 600 mL of ddH2O.
2. Slowly add 11.42 mL glacial acetic acid.
3. Add 20 mL 0.5 M EDTA, pH 8.
4. Bring up the volume to 1 L with ddH2O.

2. TBE

Tris, Borate, EDTA is used routinely for polyacrylamide electrophoresis of nucleic acids. The 1X working solution is 40 mM Tris-borate/1 mM EDTA pH 8. We will make 5L of a 1x TBE. Higher concentrations of TBE (5X and 10x) tend to crash out of solution over time.

Recipe (1L)(pH 8.3):

Component	5X TBE	10X TBE
Tris Base	54.0 g	108 g
Boric Acid	27.5 g	55 g
0.5M EDTA (pH 8.0)	20.0 mL	40 mL

3. TGS

Tris, Glycine, SDS is used for SDS-PAGE denaturing protein gels. The 1X working solution is 25 mM Tris-chloride, 192 mM glycine and 0.1% SDS, pH ~8.6. We will make 5L of a 10x TGS solution and dilute it to 1x prior to running protein gels.

Recipe (2L):

Component	Powder to add	Final Concentration
Tris Base	60.4 g	250 mM
Glycine	288.0 g	1.92 M
SDS Powder	20.0 g	1%