I am having trouble visualizing my bands in agarose gel (0.8%, 1 uL of Ethidium Bromide). I'm running PCR products (350-500bp) and I can visualize the band immediately I put it on the UV lamp (after 45' of running), but 5 mins later I canīt see almost none of them. I also tried an ethidium bath (2uL/200mL water) for 5', 10' and 30'; bands become more fluorescent with time.
And I guess I canīt see some of them from the beginning, because of this trouble and not caused by a non presence of PCR product.
Thanks a lot!!