Ethidium precipitation in CsCl Maxiprep - (Dec/02/2012 )
Anyone know what might cause the ethidium to precipitate to the bottom of the ultracentrifuge tube during a CsCl maxiprep?
It's happened repeatedly over the last few weeks, with several different cultures; there are small/no bands visible as well, despite having the expected size pellet during all of the preceding steps.
It's very strange and frustrating, any insight would be much appreciated.
Could be bound to short degraded DNA? (just an idea, don't have any real answer...)