RNasin® Plus RNase Inhibitor does not contain these cysteine residues, which makes it more resistant to oxidative damage. RNasin® Plus RNase Inhibitor forms a stable complex with RNases, inactivating the RNase. This complex is stable at temperatures up to 70°C for at least 15 minutes (Figure 1). RNasin® Plus has been tested in RT-PCR and