Ethidium Bromide POLL - Does anyone nuke their agarose w/ EtBr (Apr/19/2005 )
Just trying to get a feel for what people are doing out there.
1. Is anyone making gels by microwaving agarose with EtBr already in the TAE or TBE solution? Or do you add the EtBr after microwaving?
2. Do you cast your gels in a hood or on the bench?
3. What is your lab's general protocol for handling EtBr?
Thanks in advance.
Supposedly EtBr has recently been downgraded from Carcinogen to Irritant. However, I have not changed my handling procedures. I am leery of anything that intercalates into my DNA.
We dont microwave agarose with EtBr, so as not to send the stuff into the air. I dont want it in my lungs.
We pour our gels on a specified bench, away from high traffic, and we try not to linger while it is cooling, again so as not to inhale the fumes. Also, we dont do any other science at the EtBr bench. We reserve specific pipettmen for EtBr/DNA work.
Our EtBr waste protocol is determined by our university's health and safety, which requires us to collect all used TAE/TBE buffer for their disposal. The gels go into a specific EtBr solid waste container, which is collected by H&S for special disposal.
I am not terrified of the stuff, but I try and minimize my exposure at all times.
1. Is anyone making gels by microwaving agarose with EtBr already in the TAE or TBE solution? Or do you add the EtBr after microwaving?
2. Do you cast your gels in a hood or on the bench?
3. What is your lab's general protocol for handling EtBr?
Thanks in advance.
1, Nuke first, add EtBr after.
2, Solution made up in a fume hood, gels cast on contaminated bench.
3, Keep a seperate contaminated area for EtBr work. We tape off a biohazard area on the bench for gel casting etc. and only use it for that. Glove up for handling anything that lives in that area. EtBr waste is charcoal-filtered and incinerated.
Compared to some of the other stuff I use (TTX, Ouabain and the like) EtBr is small potatoes, but that's no reason not to take a little care with it.
B3ka.
I add EtBr (very sparingly) to my gel, just before pouring it. Sometimes i add some to my running buffer too, cast my gel on the bench and set in the fridge. We dont really have any protocols for handling it apart from the obvious gloves and just being careful.
Jon
hi
i add etBr before microwave and there's no problem with it
i would strongly recommend to pour gel under a hood, in a dedicated area.
Buffer must be filtered with activated carbon columns in order to remove etbr dissolved in them.
Then solid material in contact with etbr should be handled in a special waste and incinerated in a proper way. Normally fumes should be filtered too by the industry that burns your wastes. But it's never done.
Fred
For mnqcljsm : adding etbr in your buffer will not force etbr to get in your gel, will it?
I agree with Finnbarr ... if you microwave solutions with EtBr, it will become an aerosol that you can breathe in. It will intercalate DNA ... do you really want that to occur to the cells in your lung?
Add just before you pour the gel ... it's the safest bet 
The reason i put EtBr in my buffer aswell as my gel is becuase it moves to the -ve electrode so that the bottom of the gel doesn't show up under UV. When i add it to the buffer it makes the bottom of the gel easier to see.
1. I nuke the agarose then add the ethidium bromide
2. I pour the gels at my bench
3. We have seperate receptacles for the specific disposal of ethidium bromide.
