Can a UV crosslinker be used on enzymes, reagents and liquids in general? - (May/21/2008 )

I am based in a molecular ecology laboratory and am planning to extract DNA from and genotype modern and museum specimens of the same species. Obviously the potential for cross-contamination here is huge.

I work under a UV hood and so my equipment is sterilised under a UV crosslinker before use. I was wondering if enzymes (such as proteinase K and Taq) and PCR reagents (i.e. dNTPs) can also be treated in this way or would their efficacy be adversely affected? I know a number of people that sterilise their extraction buffer under UV but I have recently read some product information that states that a crosslinker cannot sterilise liquids.

So, does a UV crosslinker work on liquids? If so, can it be used on enzymes and reagents to help prevent contamination?

Many thanks

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I don't think anybody does UV sterilization of enzymes, although I am not sure the dosage you want to deliver would be sufficient to crosslink and reduce the efficiency. I would still like to know what other people think.

May be you should look up some ancient and forensic DNA isolation procedures and you may find some clues regarding cross-contamination issues.

Ancient DNA: http://search.vadlo.com/b/q?sn=158621799&a...ation&rel=0

Forensic DNA: http://search.vadlo.com/b/q?sn=158621799&a...c+DNA&rel=0

Museum specimen DNA: http://search.vadlo.com/b/q?sn=158621799&a...ation&rel=0

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UV can be used to sterilize liquids, depends on wavelength, power of UV-source, turbidity of liquid, thickness of liquid layer, etc. how long it should be irradiated.
For dNTPs I would not use it, they are much too susceptible. Proteins may be denaturated (?), depends perhaps on their stability, but proteinase K is very stable, I guess it can stand it. Most buffers anyway.
But PCR reagents are sterile (or were, before use), so there is no need to sterilize them. If they are contaminated with DNA, MOs, etc I would replace them.

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