I didnt see any band on my gel (1.5% agarose) for all my samples including the ladder, what could be the problem?

I did my PCR and ran the gel on the second day, I saw a very faint band ( that is more r less invicible) and this also include the DNA ladder, what could be the problem. I have used this ladder...

12 December 2019 4,790 3 View