TE buffer

TE buffer is a commonly used buffer solution in molecular biology, especially in procedures involving DNA, cDNA or RNA. "TE" is derived from its components: Tris, a common pH buffer, and EDTA, a molecule that chelates cations like Mg²⁺. The purpose of TE buffer is to solubilize DNA or RNA, while protecting it from degradation.

Recipe

A typical recipe for making 1X TE buffer is:

• 10 mM Tris, bring to pH 8.0 with HCl
• 1 mM EDTA

TE buffer is also called as T₁₀E₁ Buffer, and read as "T ten E one buffer". To make a 100 ml solution of T₁₀E₁ Buffer, 1 ml of 1 M Tris-HCl (pH 8.0) and 0.2 ml EDTA (0.5 M) and made up with double distilled water up to 100ml.

Based on nuclease studies from the 1980s, the pH is usually adjusted to 7.5 for RNA and 8.0 for DNA. The respective DNA and RNA nucleases are supposed to be less active at these pH values, but pH 8.0 can safely be used for storage of both DNA and RNA .

EDTA further inactivates DNAse, by binding to metal cations required by this enzyme.^[1]

Genomic and plasmid DNA can be stored in TE Buffer at 4°C (39.2°F) for short-term use, or -20°C (-4°F) to -80°C (-112°F) for long-term storage. Repeated freeze-thaw cycles should be avoided.^[2]

See also

• LB buffer, lithium borate buffer, a similar buffer containing lithium ions in place of Tris
• TAE buffer and TBE buffer are often used in procedures involving nucleic acids, the most common being electrophoresis.

References

ph7.4 TE buffer=100mM/L Tris(pH7.4)+10mM/L EDTA(pH8.0) from Molecular Cloning: A Laboratory Manual

1. ↑ Yagi; Horio, Shimogaki, Tokuda, Maeda (1996). "The role of DNase and EDTA on DNA degradation in formaldehyde fixed tissues". Biotechnic & histochemistry 71 (3): 123–129. PMID 8724437. 
2. ↑ Ross; Haites, Kelly (1990). "Repeated freezing and thawing of peripheral blood and DNA in suspension: effects on DNA yield and integrity". Journal of Medical Genetics 27 (9): 569–570. doi:10.1136/jmg.27.9.569. 

External links

• "OpenWetWare: TE buffer". Retrieved July 2, 2006.