Figure 7.
Lyophilization and storage of oPACE/DNA polyplexes. oPACE9-20/pLuc polyplexes were lyophilized with trehalose of different concentration. (A) The gene transfection efficiency of the lyophilized polyplexes was tested on U87MG cells with a luciferase assay, and (B) their diameter was measured with DLS. The freshly prepared polyplexes were included for comparison. In another study, oPACE9-20/pLuc polyplexes were lyophilized with 0, 15 or 30 mg/mL of trehalose and stored at -20°C for 0, 7, 14, or 30 days. Their (C) gene transfection efficiency on U87MG cells and (D) diameter before and after storage was measured. Error bars indicate standard deviation (n=3, ***: p<0.001, ****: p<0.0001, ns=no significant difference, all indicating statistical difference with fresh polyplexes).