Figure 5.
Effect of the complexation method on the transfection efficiency of pDNA/lPEI complexes at N/P 30 in L929 cells. (a) Transfection efficiency of pDNA/lPEI complexes as a function of the order of mixing and volumes of lPEI and pDNA solutions. Complexes were prepared by adding 160 ng/cm2 of pGL3 with the lPEI solution in 10 mM Hepes (DNA to PEI), or vice versa (PEI to DNA), then mixing the two solutions by rigorous pipetting, or by mixing equivolumes of DNA and PEI solutions (v/v). (b) Transfection efficiency of pDNA/lPEI complexes as a function of the complexation method. Complexes were prepared by adding 160 ng/cm2 of pGL3 to lPEI in 10 mM Hepes by single dripping, mixing (i.e., repeated and rigorous pipetting), and vortexing. Results are expressed as mean ± SD (n ≥ 3) (* p < 0.05).