Norgen's RNA purification kits isolate total RNA with minimal amounts of genomic DNA contamination. However, for some sensitive downstream applications, it may be desirable to remove all traces of residual DNA. Norgen's RNase-free DNAse I Kit can be used for optional on-column DNase digestion with any of Norgen's RNA purification kits. DNase treatment can also be performed in solution. Norgen’s Proteinase K Solution is provided in a specially prepared storage buffer that is stable and ready-to-use. This Proteinase K solution is ideal for protease digestion during DNA and RNA preparation. Norgens’ DNase-free RNase A is used for the digestion of RNA during DNA preparation.