Ambion RNase Cocktail is a mixture of two highly purified ribonucleases, RNase A (500 U⁄ml) and RNase T1 (20,000 U⁄ml) and is free of DNase and nicking activities. Use RNase Cocktail for all situations where it is desirable to degrade RNA, i.e. plasmid minipreps and ribonuclease protection assays. RNase Cocktail is supplied in 50% glycerol for maximum convenience. Digestion of RNA with RNase A alone leaves fragments of RNA which are large enough to be visible on agarose gels and precipitate in ethanol. RNase A cuts after C and U residues, and RNase T1 cuts after G residues. Consequently, the mixture of both enzymes results in a reduction in RNA fragment size over the use of either alone.

Quality control
RNase Cocktail Enzyme Mix is rigorously tested for contaminating nonspecific endonuclease, exonuclease, and protease activity. Functionality is determined in a ribonuclease protection assay.

Unit definitions
RNase A: One unit of RNase A is the amount required to give an increase in absorption at 286 nm of 0.0146 absorbance units per minute in a 1 mL volume. Unit assay conditions: 100 mM Tris-acetate (pH 6.5), 1 mM EDTA and 1 mM cyclic 2', 3'-CMP.

RNase T1: 100 Units of RNase T1 is the amount of enzyme that yields an increase in absorption at 260 nm of 0.01428 units per min at room temperature using 60 μg⁄mL yeast total RNA as a substrate.

We also offer Ambion RNA-Grade ribonuclease T1. For more information, see RNase T1 (1 U/μL) (Cat. No. AM2283).