Ambion™ Recombinant RNase A for the preparation of plasmid DNA essentially free of host RNA is now available for research applications. For larger batches, the use of RNase remains an effective technique for removing host RNA. Other methods, such as selective precipitation, gel filtration, chromatography, and endogenousE. coli RNase digestion, are only effective for small- or laboratory-scale purifications. The new product has been specifically designed to minimize the risk of introducing pathogens into bioprocesses. Recombinant RNase A is rigorously tested for contaminating non-specific endonuclease, exonuclease and protease activity.