TBE buffer

TBE or Tris/Borate/EDTA, is a buffer solution containing a mixture of Tris base, boric acid and EDTA.

In molecular biology, TBE and TAE buffers are often used in procedures involving nucleic acids, the most common being electrophoresis. Tris-acid solutions are effective buffers for slightly basic conditions, which keep DNA deprotonated and soluble in water. EDTA is a chelator of divalent cations, particularly of magnesium (Mg2+). As these ions are necessary co-factors for many enzymes, including contaminant nucleases, the role of the EDTA is to protect the nucleic acids against enzymatic degradation. But since Mg2+ is also a co-factor for many useful DNA-modifying enzymes such as restriction enzymes and DNA polymerases, its concentration in TBE or TAE buffers is generally kept low (typically at around 1 mM).

Composition (10X solution)

 * Tris (CAS# 37186)   107.78 g/l (0.89 M)
 * EDTA-Na2-salt (CAS# 39761)  7.44 g/l (0.02 M)
 * Boric acid (CAS# 11280)  55.0 g/L (0.89 M)

TBE-Puffer Tris, Borate, EDTA