Protocol used to concentrate poly(A)+ mRNA, RNA, DNA. Also to clean reactions from buffers and others that may interfere in dowstream reactions.
1. Add 1/10 volume 3 M NaAc (Sodium acetate) and 3 volumes of cool ethanol 95% (high purity bottle).
2. Mix well and incubate at -20°C for at least 20 min.
3. Centrifuge at > 12,000 x g in a microfuge for 20 minutes (if RNA work at 4°C.)
4. Discard the supernatant and wash the pellet twice with 70% ethanol (500 uL, 3 min centrifuge).
5. Air dry pellet. Check for dryness before proceeding. (no ethanol should be seen)
6. Resuspend pellet in RNase-, DNase-free H2O. Shake well, spin 5 seconds a couple of times. Let stand in ice 20 minutes.
The appropriate volume for resuspension depends on the expected yield and the amount of RNA/DNA required for your experiment (like for electroporation dissolve in 5 uL, for miniprep 30-50uL).
7. Store the solution at -80°C/RNA, -20°C/DNA.
8. If needed, quantitate by spectrophotometry and electrophoresis.