TE buffer
TE buffer is a biochemical buffer that consists of an aqueous solution of TRIS and EDTA .
properties
TE buffers usually contain a concentration of TRIS between 10 and 100 mM and a concentration of EDTA between 5 and 10 mM. In addition to adjusting the pH to 7 to 8, the EDTA also acts as a chelator for divalent cations such as B. calcium , magnesium and zinc ions , which are cofactors for various degrading enzymes such as nucleases and metalloproteases , which inhibit them. Therefore, TE buffer is suitable as a storage solution for DNA, e.g. B. after a DNA purification. The EDTA component also inhibits various other DNA-modifying enzymes with divalent cations such as DNA polymerases , which is why the DNA and thus also the EDTA is usually diluted below 1 mM EDTA before a polymerase chain reaction or isothermal DNA amplification with double-distilled water, since the typical magnesium ion concentration there is 2 to 3 mM and less than 1 mM EDTA leaves enough magnesium ions.
A modification of the TE buffer is the TSE buffer , which also contains sodium chloride . Buffers composed similarly to the TE buffer are the TAE buffer and the TBE buffer which are used for agarose gel electrophoresis .
literature
- Friedrich Lottspeich , Joachim W. Engels , Solodkoff Zettlmeier Lay: Bioanalytik . 3rd edition, Spektrum, Heidelberg 2012, ISBN 978-3-8274-0041-3 .
- Cornel Mülhardt: The Experimenter: Molecular Biology / Genomics. Sixth edition. Spectrum Akademischer Verlag, Heidelberg 2008, ISBN 3-8274-2036-9 .
- J. Sambrook , T. Maniatis , DW Russel: Molecular cloning: a laboratory manual. 3rd edition, Cold Spring Harbor Laboratory Press, 2001, ISBN 0-87969-577-3 .
Individual evidence
- ↑ N. Yagi, K. Satonaka, M. Horio, H. Shimogaki, Y. Tokuda, S. Maeda: The role of DNase and EDTA on DNA degradation in formaldehyde fixed tissues. In: Biotechnic & histochemistry: official publication of the Biological Stain Commission. Volume 71, Number 3, May 1996, pp. 123-129, PMID 8724437 .
- ↑ KS Ross, NE Haites, KF Kelly: Repeated freezing and thawing of peripheral blood and DNA in suspension: effects on DNA yield and integrity. In: Journal of Medical Genetics. 27, 1990, p. 569, doi : 10.1136 / jmg.27.9.569 .