Fig. 5
Characterization of NPs. a Hydrodynamic diameter (blue) and zeta potential (red) of different NPs over 15 days. b The hemolysis ratio of PEG-PLGA-AL@Fe3O4/E2 NPs of different concentrations incubated with RBCs. c In vitro cytotoxicity of NPs against HUVECs after treatment for 24 h (n = 3). d In vitro release profile of E2 from PEG-PLGA-AL@Fe3O4/E2 induced by external heating at 25 °C, 37 °C and 45 °C. The data are presented as mean ± SD (n = 3)