Protocol Online logo
Top : New Forum Archives (2009-): : General Lab Techniques

Plasmid Miniprep - (Nov/19/2012 )

Growing bacteria for plasmid minipreps usually requires a 12-16hr incubation. Longer incubation can cause cell lysis and loss of plasmid. Too short of incubation means less growth and less plasmid. Sometimes I don't have time to miniprep when the bacteria are ready, especially when I have 20 samples or so. Is there a good stopping point? I was wondering if I could remove my culture at 12-16 hours, pellet the cells, aspirate the media and refrigerate or freeze the pellet until I have time to do the miniprep? I thought this would be ok as long as the media is completely removed otherwise the cells would lyse during the freeze-thaw and release plasmid which would be lost during aspirating.


I've done what you just described (pellet, aspirate media, freeze), and the subsequent mini-prep worked just fine.


Yes, common method for keeping bacterial pelets before plasmid isolation. OK for (at least) weeks. Let the bacteria thaw directly by adding lysis solution and mixing after that.