how to prepare RNAse A from powdered form - (Sep/03/2009 )

how to prepare RNAse A from powdered form for use in DNA extraction purification

Try this:

Dissolve RNAse A at a concentration of 10 mg/ml in 0.01M sodium acetate (pH 5.2);
Heat to 100°C for 15 minutes;
Allow to cool slowly to room temperature;
Adjust the pH by adding 0.1 volumes of 1M TrisHCl (pH 7.4);
Dispense into aliquots and store at -20°C.