Hello researchers. I am using CTAB method to extract total genomic RNA from Citrus leaves. I often observe that the pellet is very minute and keeps floating which makes it difficult to discard the supernatant. I want to know what could be the possible reasons for getting a floating pellet and how to avoid it. Thank you.
You could try spinning for longer to get the pellet to stick a bit better to the tube. Some starting materials are just less "sticky" than others. Also, make sure your centrifuge is getting up to the high speed. I had issues with an older centrifuge that just wouldn't spin fast enough anymore & lost pellets. Maybe a newer/different centrifuge?
You could carefully transfer the pellet to a new tube, rather than decanting the supernatant.
Good luck!
You could try adding an inert co precipitant such as glycogen or linear acrylamide giving you a larger precipitate which will spin down more easily
After adding ethanol/isopropanol (ice-cold) the tubes (2.0 ml vials, I guess) may be spinned at a speed of 12000 rpm or more for 10 min, which should give an intact pellet of RNA (or DNA in case of DNA isolation). Do not use pipette for discarding the supernatant. Simply discard by inverting the tube without disturbing the pellet. Immediately place the mouth of the tube on a tissue paper.
- Badges
- Science topic
- Similar topics
- Phytochemistry
- Extracts