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Etbr in agrose Gel - (Sep/02/2006 )

hi all, i just want to know if u forget to add Etbr in agrose soln then can we add it in the buffer used as coolant for running the gel.


We add EtBr to visualise DNA. So u could add it to the gel before visualising it.


you may also add tiny amounts of EtBr to your samples when loading

if you choose to stain after running the gel, you simply make a solution of EtBr in buffer and soak the gel; then de-stain with water or buffer before taking the picture


You can add it to the buffer but you have to add it to the tank furthest from the wells. EtBr runs in the opposite direction of DNA so as your DNA is running to the positive electrode the EtBr will run to the negative. This doesn't usually stain your gel as well as soaking it in an EtBr solution after running the gel but it still works. If you are trying to visualize faint bands though I would stain the gel after running it.


i think staining afterrunning the gel is the convenient solution for your problem.
If not, just remelt the agarose and add EtBr. it's quick too.


I very much perfer to do my EtBr staining after running my gel.

In this manner you keep both the electrophoresis equipment and the wet working area of the lab EtBr free. There is always the risk of spillage when working with the buffer solutions, pouring the agarose and when the need to remelt the agarose arises.

In my lab we have an EtBr bath away out from busy areas of the lab. We reuse the same bath for a week and sometimes more.