Why can I not see bands on an agarose gel? - agarose gel visualization (Jul/09/2006 )
I am new to molecular stuff and am attempting to visualize my DNA after PCR using an agarose gel. I did PCR with positive and negative controls using a Promega kit but in running the results on the gel afterwards I see nothing -- no bands at all. I also ran a Promega supplied allelic ladder and see nothing in that lane either. I assume that I do not have to put the ladder sample through PCR but just put it in the well with dye? I am using the EtBr packaged strips that you press on the gel after running as the visualization technique. Any ideas why I see nothing?
this might be a dumb question, but you did use a UV light source, right? and what about the gel? did you make and pour it yourself? please walk us step-by-step through the gel making/pouring/running that you did so we can help find your mistake
good luck!
see if you can repeat your experiment by reversing electrodes.
Too many variables to cooment on any one factor.
As aimikins suggested, please b more specific.
Hi Steve,
Yes, did you prepare the gel yourself? Make sure you put in TAE buffer (not water). What is the Etbr package and how did you use it? Did you allow it to diffuse into the gel and bind to the expected DNA for a while (say, 15 min.)?
Charles
and check the wavelength setting of your UV box, if it has one.
we switch around all the time at our lab, so if i have an empty gel, i usually check this....