TE buffer is a commonly used buffer solution in molecular biology, especially in procedures involving DNA 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.
A typical recipe for making 10:1 TE buffer is:
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 make up with double distilled water up to 100ml.
Based on nuclease studies from the 1980's, 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 nucleases, by binding to metal ions required by these enzymes.
The best temperature for genomic DNA storage in TE Buffer is 39.2 F (4ºC).