QIAGEN RNase Inhibitor (500 reactions) QIAGEN RNase Inhibitor is a protein of nonhuman origin that binds noncovalently to an inactivates a variety of ribonucleases (e.g., RNase A, B, and C). It does not interfere with RNase T1,T2, H, U1, U2, or CL3. QIAGEN RNase Inhibitor is a polyclonal antibody which is highly active and inhibits more than 90% of RNase activity, whereas HPRI (human placental RNase inhibitor) inhibits only 50%. For this reason, it can be used at lower concentrations compared to other RNase inhibitors. In addition, QIAGEN RNase Inhibitor is stable over a wide pH and temperature range and at varying dithiothreitol (DTT) concentrations. QIAGEN RNase Inhibitor is supplied at a concentration of 4 units per microliter in 2 mM KH2PO4, 8.0 mM Na2HPO4, 3.0 mM KCl, 150 mM NaCl, pH 7.4, and 50% glycerol.