Figure 2.

In vitro and in vivo characterizations of DNA/FTS-PEI nanocomplexes

(A) The hydrodynamic sizes and zeta potentials of FTS-PEI micelles (5% FTS, PEI MW = 2.5 kDa) and expression plasmid (p)GFP/FTS-PEI nanocomplexes formed at various N/P ratios. (B) Gel retardation assay of pGFP/FTS-PEI nanocomplexes at different N/P ratios. Samples were incubated for 20 min at room temperature prior to electrophoresis on a 1.5% (w/v) agarose gel (120 V, 20 min). (C) Gel electrophoresis assay of DNA displacement from pGFP/FTS-PEI nanocomplexes (N/P = 1) by dextran sulfate at various S/P ratios. (D) Linear PEI (MW = 2.5 kDa or 25 kDa) conjugated with different percentages of FTS (1% or 5%) were complexed with pGFP at N/P ratios of 0.5/1, 1/1, and 2.5/1, respectively. A total of 12 nanocomplexes were obtained that vary in the FTS/PEI (m/m) as well as N/P ratios. Nanocomplexes were individually administered via intratumor injection into tumor-bearing mice. Tumor tissues were collected after 48 h, and transfection efficiency was evaluated by fluorescence microscopic examination of GFP expression.