LiCl in DNA prep

[Dom Spinella]

Rodney:
LiCl can be used to remove RNA from DNA preps.  Large RNAs (rRNA, 
mRNA, etc.) are insoluble in solutions with high salt concentrations 
(and its easiest to achieve high concentration with LiCl because it is 
more soluble than NaCl), while DNA and small RNAs remain soluble.  
Typically one must adjust the LiCl concentration to 4M to achieve the 
differential "salting out" of RNA.  The more common use of LiCl is to 
purify the RNA from contaminating DNA, but the procedure can be used 
in either direction. Hope this helps. 
D.G. Spinella, Ph.D.