Fig. 3.
In vitro disassembly analysis of MNP in the interior of contact-inhibited and dividing endothelial cells. MNP stably labeled with BODIPY558/568 exhibit complex excitation and emission patterns (A and B, respectively) suggesting partial aggregation of the fluorophore to form a species with red-shifted emission (λ = 612 nm) in intact MNP. Forced degradation of MNP with Proteinase K results in a readily quantifiable decrease in the ratio of fluorescence intensities at λ = 612 and 575 nm (C). This phenomenon was used for examining directly and non-invasively disassembly rates of polylactide-based MNP in the interior of contact-inhibited and dividing endothelial cells (D). Data in C and D are presented as mean ± SD.