I am looking for a propper protocol for RNA extraction from breast tissue. I did couples of trials and it didn't work. I got RNA quantity, conce= 40ng/ul 260/280= 1.98 and 260/230= 1.7. BUT when checking the quality in denaturing MOPS gel, the results were big chunck of DNA above the wells and no signs of the RNA subunit bands.
I did DNAse1 treatment, the results were the same.
I am using tissue frozen in liquid nitrogen. I tried pistle and mortor homogenization and polytron, and the results were the same.