[Treitli Sebastian]

Hi,

 

My personal experience (especially with SeraMag Beads) is that the binding capacity of the carboxylated beads in guanidine buffers is more reduced. When I was using SeraMag carboxylated beads to purify plasmid DNA according to the protocols described here (#5.1) I always got low amount of plasmid-DNA recovered compared to a control (like column method). The moment when I removed the guanidine buffer and used PEG buffers, the protocols started to work much better.

Now, the protocols.io link which you posted suggests that the beads are prepared in a PEG buffer, however, I think the guanidine salt causes some issues and this is why you have low recovery. Among things which I would try, would be to add more beads (make  the stock solution more concentrated, like use 2 mL of beads /50 mL of stock solution when you prepare the beads), or don’t use SeraMag carboxylated beads, but try to adapt a protocol with silica coated beads from here. Silica works better in guanidine buffers, and it might solve your issue.

 

Best regards,

Sebastian

[Author]

Posts