TAE and TBE Running Buffers Recipe & Video

What are Tris Acetate EDTA and Tris Borate EDTA?

Tris acetate EDTA (TAE) and tris borate EDTA (TBE) are the two most common running buffers used in nucleic acid electrophoresis. As buffers, they have a fairly constant pH and are able to conduct electricity because of their concentration of hydrogen ions. These properties are necessary for gel electrophoresis during which proteins are separated by electric charge.

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Preparation Video Recipes
Applications Comparison Chart
Video Transcript

Preparing Running Buffers

TBE and TAE are most often mixed from their constituent parts into laboratory stock solutions. Both buffers can be purchased at the working concentration or in a powdered or concentrated format that is simply prepared via dilution.

Refer to the recipes below to prepare TAE and TBE in common stock solution concentrations. Our buffer calculator can also help you find the correct dilution (or conversion) for various buffers from stock solution to a desired molarity and volume.

Video: TAE and TBE Buffers for Gel Electrophoresis

Review common TAE and TBE buffer solution recipes and learn which running buffer to choose for your nucleic acid gel electrophoresis application. Research technology specialist Chris Lemke mixes up stock solutions and provides helpful buffer selection tips.


This video was built in collaboration with Seeding Labs, a nonprofit that connects universities and research institutes in developing countries with high-quality surplus lab equipment, training, and professional exchanges.

A video transcript is available below.

TAE Buffer 50x Stock Recipe

  • 242 g tris base in double-distilled H2O
  • 57.1 ml glacial acetic acid
  • 100 ml 0.5 M EDTA solution (pH 8.0)

Adjust volume to 1 L.

10x TAE Recipe

For 1L of 10x solution,

  • 48.5 g tris
  • 11.4 mL glacial acetic acid
  • 20 mL 0.5M EDTA (pH 8.0)

1x TAE Recipe

Dilute 1:10

  • 0.4 M tris acetate (pH approximately 8.3)
  • 0.01 M EDTA

using ultrapure water.

TBE Buffer 10x Stock Recipe

  • 108 g tris base
  • 55 g boric acid
  • 900 ml double-distilled H2O
  • 40 ml 0.5 M EDTA solution (pH 8.0)

Adjust volume to 1 L.

1x TBE Preparation

Dilute 10x concentrated TBE buffer 10-fold with ultrapure water.

The final solution should contain:

  • 0.13 M tris (pH 7.6)
  • 45 mM boric acid
  • 2.5 mM EDTA

Buffer Prep Tips

  • If precipitation is present, warm to 37 °C and mix until completely dissolved prior to dilution.
  • It is recommended 1x working solutions be filtered through a 0.2 mm filter before use.
  • 1x working solutions can be used until the expiration date on packaging with storage at room temperature. Discard if buffer becomes cloudy or discolored.

TAE vs. TBE Comparison Chart

  TAE Buffer
TBE Buffer
Buffering Capacity High Low TAE becomes exhausted during extended or repeated electrophoresis.
Migration of DNA Slow Fast TAE has better conductivity.
Resolution High resolution of >2KB DNA fragments  High resolution of <2KB DNA fragments TBE supports agarose cross-linkage.
Enzyme Inhibitor Yes No Borate from TBE inhibits many enzymes.
Cost Higher Lower  


Tris-acetate-EDTA (TAE) running buffer and tris-borate-EDTA (TBE) are commonly used buffers for DNA agarose gel electrophoresis that are especially useful in preparative work.1

Compared to tris-borate-EDTA (TBE) and tris-phosphate-EDTA (TPE) buffers, double-stranded DNA tends to run faster in TAE. However, because TAE has the lowest buffering capacity of the three buffers, the buffering capacity can become exhausted during extended electrophoresis. Buffer circulation or replacement can remedy this situation.


The 1x TAE buffer is used both in the agarose gel and as a running buffer. Applied voltages of < 5 V/cm (the distance between the electrodes of the unit) are recommended for maximum resolution.2

TAE buffer has been utilized in agarose gel electrophoresis of RNA.3,4

A study of free DNA solution mobility in TAE at various buffer concentrations, in the presence and absence of added NaCl, has been reported.5

The use of TAE buffer in a denaturing gradient gel electrophoresis method for broad-range mutation analysis has been described.


TBE buffer is recommended for resolution of RNA and DNA fragments smaller than 1500 bp.

TBE is used with both non-denaturing or denaturing (7 M urea) gels.

It is also routinely used for DNA automated sequencing gel.

Tris-borate-EDTA buffer has been used for pulsed-field gel electrophoresis (PFGE). Applied voltages of less than 5 V/cm are recommended for maximum resolution.

Transcript: Gel Electrophoresis Buffers

Hello, my name is Chris Lemke. I work for the life science business of Merck KGaA, Darmstadt, Germany. I'm a research technology specialist, and I live in Charlotte, USA.

In this video, I will discuss gel electrophoresis buffers, specifically:

  • Why are they needed?
  • What are the most common types? 
  • Which type is right for your application?

So when you're running a gel, the buffer is needed for two primary reasons:

  1. First, the buffer provides ions and these ions carry the electrical current through the gel.
  2. But second, the buffer acts as a buffer, maintaining a fairly constant pH throughout the gel run.

Now the two most common buffers used for nucleic acids are tris acetate EDTA and tris borate EDTA. So what's the difference between these two buffers, and which of these buffers is right for your application?

TAE buffer is a solution consisting of tris base, acetic acid, and EDTA. TAE Buffer is commonly prepared as a 50X concentrated stock.

To make the stock, dissolve 242 grams of tris base into distilled deionized water. Add 57.1 milliliters of glacial acetic acid. Then add 100 milliters of 0.5 molar EDTA solution at a pH of 8.0. Then bring the final volume up to 1 liter total, using distilled deionized water.

TBE buffer is a solution consisting of tris base, boric acid, and EDTA. TBE buffer is commonly prepared as a 10X concentrated stock.

To make the stock solution, dissolve 108 grams of tris base and 55 grams of boric acid into 900 milliliters of distilled deionized water. Then add 40 milliliters of 0.5 molars EDTA solution at a pH of 8.0. Then bring the final volume up to 1 liter total using distilled deionized water.

So which buffer is right for your application?

  • TBE buffer has better buffering capacity than TAE, so if you'll be doing extended long runs or repeated runs in the same buffer, you'll want to use TBE buffer.
  • TAE buffer has better conductivity than TBE, so DNA fragments will migrate faster in TAE buffer than TBE.
  • TBE buffer supports better agarose cross-linkage, so you'll get better resolution of large DNA fragments in TBE buffer and better resolution of smaller DNA fragments in TAE buffer.
  • The borate in TBE buffer inhibits many common enzymes used in molecular biology, so if you'll be using the DNA for any downstream applications involving an enzyme, like PCR or clonal ligation, you'll want to use TAE buffer.
  • And finally, TBE buffer costs more to make than TAE buffer.

Thank you for watching. I hope this helps.


Bionic Buffer is a unique alternative to traditional TBE (tris-borate-EDTA) and TAE (tris-acetate-EDTA) electrophoresis buffers. Bionic Buffer allows for:

  • Band resolution in minutes
  • Running gels 2-3x faster than in TBE/TAE
  • Sharper bands in less time
  • Use with pre-cast gels


1. Ogden, R. C., and Adams, D. A., Electrophoresis in agarose and acrylamide gels. Methods Enzymol., 152, 61-87 (1987).

2. Molecular Cloning: A Laboratory Manual, 3rd ed., Sambrook, J. and Russell, D. W., CSHL Press (Cold Spring Harbor, NY: 2001), pp. 5.8, 5.76, A1.16.

3. Loening, U. E., The fractionation of highmolecular-weight ribonucleic acid by polyacrylamide-gel electrophoresis. Biochem. J., 102, 251-257 (1967).

4. Masters, D. B., et al., High sensitivity quantification of RNA from gels and autoradiograms with affordable optical scanning. Biotechniques, 12(6), 902-906, 908-911 (1992).

5. Stellwagen, E., and Stellwagen, N. C., The free solution mobility of DNA in Tris-acetate-EDTA buffers of different concentrations, with and without added NaCl. Electrophoresis, 23(12), 1935-1941 (2002).

6. Hayes, V. M., et al., Improvements in gel composition and electrophoretic conditions for broad-range mutation analysis by denaturing gradient gel electrophoresis. Nucleic Acids Res., 27(20), e29 (1999).


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