View source for Chemistry:TAE buffer

{{Short description|Buffer solution}}
'''TAE buffer''' is a [[Chemistry:Buffer solution|buffer solution]] containing a mixture of Tris base, [[Chemistry:Acetic acid|acetic acid]] and [[Chemistry:EDTA|EDTA]].  

In molecular biology, it is used in agarose [[Biology:Electrophoresis|electrophoresis]] typically for the separation of nucleic acids such as [[Biology:DNA|DNA]] and [[Biology:RNA|RNA]].<ref>Ogden, R.C., and Adams, D.A., (1987) Electrophoresis in agarose and acrylamide gels. ''Methods Enzymol''., '''152''':, 61-87.</ref> It is made up of Tris-acetate buffer, usually at pH 8.3, and [[Chemistry:EDTA|EDTA]], which sequesters divalent cations. TAE has a lower buffer capacity than [[Chemistry:TBE buffer|TBE]] and can easily become exhausted, but linear, double stranded DNA runs faster in TAE.

Previously, Brody & Kern simplified electrophoretic buffers by substituting TBE and TAE buffers for a more efficient and inexpensive conductive media in gel systems.<ref>Brody, J.R., Kern, S.E. (2004) History and principles of conductive media for standard DNA electrophoresis. ''Anal Biochem.'' 333(1):1-13. {{doi|10.1016/j.ab.2004.05.054}} {{PMID|15351274}} [http://www.cc.ahs.chula.ac.th/Molmed/DNA%20electro%27s%20conductive%20media.pdf PDF]</ref>

==Uses==
TAE (Tris-acetate-EDTA) buffer is used as both a running buffer and in agarose gels.<ref>Sambrook, Fritsch, and Maniatis (1989) ''Molecular Cloning: A Laboratory Manual'', 2nd ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York, volume 3, apendices B.11 and B.23 {{ISBN|0-87969-309-6}}</ref> Its use in denaturing gradient [[Biology:Gel electrophoresis|gel electrophoresis]] methods for broad-range mutation analysis has also been described.<ref>Hayes, V.M. et al., (1999) Improvements in gel composition and electrophoretic conditions for broad-range mutation analysis by denaturing gradient gel electrophoresis. ''Nucleic Acids Res''., '''27'''(20): e29. {{PMID|10497279}}</ref> TAE has been used at various concentrations to study the mobility of DNA in solution with and without [[Chemistry:Sodium chloride|sodium chloride]].<ref>Stellwagen, E., and Stellwagen, N.C. (2002) The free solution mobility of DNA in Tris-acetate-EDTA buffers of different concentrations, with and without added NaCl.  ''Electrophoresis'', '''23'''(12): 1935-1941.  {{PMID|12116139}}</ref> However, high concentrations of sodium chloride (and many other salts) in a DNA sample retard its mobility. This may lead to incorrect interpretations of the resulting DNA banding pattern.

==Preparation==
TAE buffer is commonly prepared as a 50× stock solution for laboratory use.  A 50× stock solution can be prepared by dissolving 242 g Tris base in water, adding 57.1 ml glacial acetic acid, and 100 ml of 500 mM EDTA (pH 8.0) solution, and bringing the final volume up to 1 litre. This stock solution can be diluted 49:1 with water to make a 1× working solution. This 1× solution will contain 40 mM Tris, 20 mM acetic acid, and 1 mM EDTA.

{| class="wikitable sortable"
|-
! No.
! Name
! Per 1 mole
! 50x solution
! 50×
! 1× solution
! 1X
|-
| 1
| Tris base
| 121.1 g/L
| 2 M
| 242.2 g/L
| 40 mM
| 4.844 g/L
|-
| 2
| [[Chemistry:Acetic acid|acetic acid]]
| 57.1 ml/L
| 1 M
| 57.1 ml/L
| 20 mM
| 1.21 ml/L
|-
| 3
| [[Chemistry:EDTA|EDTA]] disodium salt dihydrate
| 372.24 g/L
| 50 mM
| 18.612 g/L
| 1 mM
| 0.372 g/L
|}

2 M = 2000 mM so 2000 mM /50 = 40 mM for 1×. <br /> 1M = 1000 mM so 1000 mM /50 = 20 mM for 1×. <br /> 50 mM /50 = 1 mM for 1×.

First of all, these ingredients should be dissolved in 500 ml, then made up to 1000 ml. <br /> Note: EDTA will take more time to dissolve, so while dissolving EDTA use magnetic stirrer (few amounts of EDTA in 3 or 4 times).

A step-by-step recipe of the preparation method for 50× TAE buffer is available on protocols.io.<ref>{{Cite journal|last1=Behle|first1=Anna|last2=Pawlowski|first2=Alice|title=Recipe for 50x TAE buffer |date=6 April 2018 |url=https://www.protocols.io/view/recipe-for-50x-tae-buffer-gtvbwn6|doi=10.17504/protocols.io.gtvbwn6}}</ref>

==See also==
* [[Chemistry:TBE buffer|TBE buffer]]
* [[Chemistry:LB buffer|LB buffer]]

==References==
<references/>
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[[Category:Buffer solutions]]

{{Sourceattribution|TAE buffer}}