Figure 1.

Physicochemical characterization of CK₃₀PEG_10k/DNA NPs. (a) Transmission electron micrograph of CK₃₀PEG_10k/DNA NPs. Bar = 200 nm. (b) Turbidity parameter as indicator of particle stability (n = 3). A turbidity parameter greater than −3.5 (dashed line) indicates complexes that are stable and nonaggregated in solution, whereas below dashed line indicates aggregated complexes. Turbidity parameter of CK₃₀PEG_10k/DNA NPs is compared to that of uncoated counterpart (CK₃₀/DNA NPs). (c) Sedimentation assay indicates nonaggregated fractions of gene carriers in saline after 2 months of storage at 4 °C (n = 3). (d,e) Stability of plasmid DNA against DNase digestion over 0, 0.5, 1, 1.5, and 2 hours (lanes 1–5). (d) Free DNA was degraded with 0.5 hour after DNase treatment. (e) Gene carriers protect compacted DNA against DNase treatment up to 2 hours. Upper and lower bands depict nicked circular and supercoiled conformations of DNA, respectively. The differences are statistically significant between the conditions indicated with asterisks (*) (**P < 0.01). Mean ± SEM.