Fig. 3.

Iron (III) citrate inhibits PEI-mediated transfection of CHO cells. CHO DXB11 cells were plated onto a six well plate in DMEM with 10% FBS. The following day, the indicated iron chelator was added to the media at a final concentration of 20 μM and cells were transfected with the vector pEGFP-N1 using PEI as detailed in “Materials and methods”. After 48 h, the cells were examined by fluorescent microscopy to determine expression of GFP. The experiment was performed three times with similar results