Fig. 5.

In vitro cellular uptake of MRC-PPL or MR-PPL micelles. a Immunofluorescence staining in chondrocytes to co-localized with collagen type II in the presence of MMP-13 or its inhibitor. The nuclei were counterstained with DAPI (blue) and collagen type II was stained with FITC (green). Scales bar: 400 μm. b Fluorescence quantification of Cy5.5 after uptake of MRC-PPL or MR-PPL micelles by cells. Scale bars: 40 µm. (n = 3; mean ± s.d; *, # indicate p < 0.05, **, ## indicate p < 0.01, ***, ### indicate p < 0.001.)