I have been using reverse transfection with invitrogen siRNA and Hiperfect transfection reagent to knockdown SRC-3 and SMRT in HeLa cells.
I have gotten the knockdown to work twice before, but then the knockdowns no longer work. Is the siRNA going bad? When its not in the freezer its on ice, but I do not know what is happening to the knockdown. It goes from 90% knockdown two experiments in a row to no knockdown from the 3rd experiment on.
Has anyone else had any similar problems?