Fig. 3

The cellular uptake ability of both PTX-PEG-PLA-NP and PTX-PEG-PLA-FA-NP in SK-OV-3, HO-8910, and A2780 cells under fluorescence microscopy. Notes: (a) The cellular uptake amounts of both PTX-PEG-PLA-NP and PTX-PEG-PLA-FA-NP (10% FA) were examined in SK-OV-3, HO-8910, and A2780 cells (co-incubated for 4 h) by fluorescence microscopy. The images showed that more PTX-PEG-PLA-FA-NP was taken up in SK-OV-3 cells than in HO-8910 and A2780 cells. Furthermore, SK-OV-3 cells had taken up more PTX-PEG-PLA-FA-NP than PTX-PEG-PLA-NP; (b) The expression levels of FRα in three ovarian cancer cell lines determined by RT-PCR testing; (c) Fluorescence density half-qualitatively analysis results in SK-OV-3, HO-8910, and A2780 cells of PTX-PEG-PLA-NP and PTX-PEG-PLA-FA-NP (10% FA contained, incubated for 4 h); (d) The fluorescence intensity of PTX-PEG-PLA-FA-NP in three different ovarian cancer cell lines under different incubation time; (e) The fluorescence intensity of PTX-PEG-PLA-FA-NP in SK-OV-3 cells with different FA concentration (5%, 10% and 20% FA); Fig. 3f showed the cellular uptake results of PTX-PEG-PLA-FA-NP in SK-OV-3 cells in different concentration FA contained culture medium (0 μg/ml, 5 μg/ml, 20 μg/ml and 50 μg/ml) by fluorescence microscopy; The images showed that more PTX-PEG-PLA-FA-NP was taken up by SK-OV-3 cells in the FA-free culture medium. With FA concentration increase from 5 μg/ml to 50 μg/ml the fluorescence signals in the SK-OV-3 cells decreased accordingly, with suggested that PTX-PEG-PLA-FA-NP uptake were FAR-specific on SK-OV-3 cells; Fig. 3g showed the fluorescence intensity of PTX-PEG-PLA-FA-NP in SK-OV-3 cells with different concentration FA contained culture medium (0 μg/ml, 5 μg/ml, 20 μg/ml, 50 μg/ml). *p < 0.05, **p < 0.01, ***p < 0.001