Do you know if jetPEI™ has been tested on L6 (rat skeletalmuscle cells) cell line before?
jetPEI™ reagent works for the transfection of C2C12 cells (murine muscle) at the myoblast stage. However, when these cells differentiate into the myotubes, they become difficult to transfect. This might also apply to L6 cells which resemble C2C12 (i.e. transfection is likely to work at the myoblasts stage but not at the myotube stage).