RNAse A

Materials

 * RNase A
 * NaOAc (0.01 M, pH 5.2)
 * Tris-Cl (1 M, pH 7.4)

Method (makes 1 mL of 10 mg/mL solution)

 * 1) Dissolve 10 mg of RNase in 1 mL of NaOAc.
 * 2) Heat the aliquot at 100 C for 15 minutes.  Heating irreversibly deactivates any DNase activity. RNase activity is similarly inhibited but returns upon cooling.  
 * 3) Allow to cool slowly to room temperature by switching off the heat source.
 * 4) Adjust the pH by adding 100 ul of Tris-Cl .   RNase precipitates when concentrated solutions are heated at 100 C at neutral pH. 
 * 5) Store at -20 C.