I extracted total RNA from HEK293 cell using Trizol, then I ran all my 3 samples on 1% TAE agarose gel for RNA quality check (Pls refer to the attached picture).

But beside 28S and 18S bands (band number 1 ans 3), I also got another band between 28S and 18S bands (band number 2), and 1 band just right belown 18S band (band number 4).

I measured RNA concentration using Nanodrop : ~935 ng/ul, 260/280 ~1.95, 260/230 ~ 2.15.

I also use DEPC water for elution.

Would you mind troubleshoot the band number 2 and 4 ? Thank you so much.