Normalized in vitro transfection efficiency (RLU/µg Protein)) and median uptake fluorescence (YOYO-1 Fluorescence) of PAMAM (a–d) and PEI (e–h) polyplexes in HeLa cells in the presence of increasing concentrations of genistein (a,e), MβCD (b,f), amantadine (c,g) or chlorpromazine (d,h). All results were normalized to polyplexes at N/P 10, under inhibitor-free conditions. (N=6; error bars represent standard deviation; *,+ = p<0.05; **,++ = p<0.01; ***, +++ = p<0.001 compared to the same polyplex in the absence of drug).