Preserving DNA Integrity in Dry State Environment
GenTegra™ DNA’s water-free environment ensures protection of DNA from degradation over a long period of storage at room temperature. When air-dried in a chemical medium with low water content, such as GenTegra, DNA becomes much more stable at room temperature. DNA is a chemical polymer that is unstable in the presence of water because of its sensitivity to the addition of water across its phosphodiester bonds which produces strand breakage¹. DNA in a bone-dry environment also diminished the rate of ultraviolet light damage. This was first noticed in the unusual stability of DNA in air-dried seeds². In the air-dried state at less than 70% relative humidity, DNA takes a coiled configuration or structure that is incompatible with ordinary UV-light induced thymidine dimer formation³, or other water aided reactions that promote UV-light photo-damage such as pyrimidine photohydrate formation, which is also slowed in the absence of water to react with the pyrimidine bases. In addition, the thick plastic of the cluster tube format provides thermal stability for DNA samples even at elevated temperatures. At the heart of it, water can be seen as the main reason for the tradition that DNA must be stored in refrigeration. In the absence of water, especially in a “bone dry” environment, much of the rationale for cryogenic storage is eliminated.
References
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lanthanide ions: mechanistic studies leading to new applications. Chem.
Comm. 1999, 1443–1451 (1999).
2. Vanhee, L.M., Nelis, H.J. & Coenye, T. Enumeration of airborne bacteria and fungi
using solid phase cytometry. J. Microbiol. Methods 72, 12–19 (2008).
3. Lamola, A.A. & Mittal, J.P. Solution photochemistry of thymine and uracil.
Science 154, 1560–1561 (1966).