Add 0.5 ml of PD1 Buffer to a RNase A tube, Dissolve the RNase A by vortexing. Briefly spin the tube and transfer the total RNase A mixture back to the PD1 bottle, mix well by vortexing and store the PD1 buffer at 4 °C.
If precipitates have formed in PD2 Buffer, warm the buffer in 37°C waterbath to dissolve precipitates.
Preparation of PDW Buffer and Wash Buffer by adding 96 ~100% ethanol (not provided) for first use.
Centrifugation steps are done by a microcentrifuge capable of the speed at 11,000 ~1,8000 x g.