proteinase K solutions

Rafael Maldonado rafael at
Fri Aug 25 13:48:42 EST 1995

On 24 Aug 1995, Howard T. Petrie wrote:

> We use proteinase K for DNA/RNA purification, etc.  We make it up at
> 20mg/ml in water and store it frozen, as all of the prominent methods
> texts recommend.  

So your proteinase K precipitated...

It happened to me all the time. B-M proteinase K precipitate when it is 
cold at 20 mg/ml concentration. We tried 5 mg/ml and the precipitation 
stopped. It is a pain get dissolved the proteinase K again, but I never 
detected a loss of activity when precipitation is present.

I realized that other proteinases from different companies don't have got 
that problem. Currently, I am using Gibco-BRL at 20 mg/ml without any 
precipitation problem. 

No relation with any of those companies, economical, sentimental, 
emotional nor musical.


Rafael Maldonado                             |  La cita ha sido
room 6160 Eccles Institute of Human Genetics |  
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