I have a RNA sample with 300 ng/uL of concentration and 260/280 as well as 260/230 ratios higher than 1.9. I ran an agarose gel to test the quality of my RNA sample and my loading buffer had a denaturing agent formamide. I followed the protocol mentioned in one of the articles about RNA electrophoresis. It says that I can run my RNA on agarose in normal TAE provided I have formamide in my loading buffer. However, I do not see any sort of band which might correspond to my RNA nor anything in the wells. What problem could this be that I am not being able to understand?