Fig. 4
From: Hydrogel-based platforms for site-specific doxorubicin release in cancer therapy
Reprinted with permission from ACS [147]
Left side) (A, B) Evaluating the internalization of free doxorubicin (0–5 µM) and doxorubicin upon release from sodium bicarbonate-loaded chitosan-PEG hydrogels at low pH (6.5) for 48 h. The development of hydrogels was based using a sodium bicarbonate concentration of 100 mM and a doxorubicin concentration of 50 µM. This gives a doxorubicin concentration of 0.47 ± 0.05 µM in the cell solution over a 48 h period. This is afluorescence microscopy images of MDA-MB-231 and MCF-7 cells. Right side) (A and B) pH-dependent localization of doxorubicin in the nucleus and related confocal fluorescence images. (C, D) The tumor cells were treated with free doxorubicin (0–5 µM) and the fluorescent intensity of drug was evaluated in the nucleus. There was an increase in the nuclear accumulation of doxorubicin. Each value represents the mean ± SE (n = 29–237, MDA-MB-231) and mean ± SE (n = 28–192, MCF-7) with significance defined as * p < 0.5; *** p < 0.001, **** p < 0.0001.