Michael van Waes bi__mvw at SELWAY.UMT.EDU
Fri Aug 26 12:28:27 EST 1994

>	I could use some help in removing trace quantities of RNA from a 
>pBluescript plasmid prep that I have.  I made a very large (15 mg) prep 
>by traditional means, and used a combination of RNASE A and RNASE T1 to 
>chew up the RNA.  I thought that that would be sufficient, but it turns 
>out that the small amount of tiny (runs below 200 bp vs. dsDNA ladder) 
>RNA remaining is a problem.  So I used a CsCl2 gradient, which removed 
>90 % the RNA, but still there is enough to cause a problem. I would 
>appreciate any suggestions for chemically gentle (non-DNA-damaging) 
>methods to remove the trace RNA contamination that remains.
>	One suggestion I have had is to run a gel filtration column.  If 
>any of you have experience with such, and could recommend the best media, 
>column conditions, etc.. I would be very grateful.  
>	Thank you in advance for your help, either as a followup post 
>here or as email to the address below.
>Marc Goldstein
>Section of Plant Biology
>U. C. Davis
>magoldstein at ucdavis.edu
 How about alkalilne hydrolysis? Just raise the pH to 10 and incubate at 65
 degrees for 30' or so. That's sure to digest the RNA without affecting DNA

 Just a thought. Good Luck!

More information about the Methods mailing list