Fig. 1

Preparation and identification of ICG/PTX@RGE-EV. A Morphological characteristics of EVs derived from Raw264.7 cells under TEM (scale bar = 100 nm). B Diameter of EVs detected by NTA. C Protein expression of EV markers, CD63, CD81, Alix and EV contamination index ApoA1 detected by Western blot analysis. D Morphological characteristics of ICG/PTX@RGE-EV under TEM (scale bar = 100 nm). E Diameter of EVs detected by NTA. F Protein expression of EV markers, CD63, CD81, Alix and EV contamination index ApoA1 in ICG/PTX@RGE-EV detected by Western blot analysis. G ICG/PTX@RGE-EV observed under super-resolution fluorescence microscopy (green fluorescence: RGE) (scale bar = 20 μm). H ICG/PTX@RGE-EV under confocal microscope (red fluorescence: EV, green fluorescence: RGE) (scale bar = 20 μm). I U251 cells incubated with CM-DiI-labeled ICG/PTX@RGE-EV observed under confocal microscope (scale bar = 20 μm). J FITC-positive cells identified by flow cytometry (i, U251 cells incubated with ICG/PTX@RGE-EV; ii, U251 cells incubated with ICG/PTX@ EV and RGE; iii, U251 cells incubated with ICG/PTX@EV; iv, free U251 cells; v, FITC-labeled U251 cells). Measurement data were expressed as mean ± standard deviation. Data comparison was analyzed by one-way ANOVA among multiple groups, followed by Tukey’s post hoc test. *p < 0.05 vs. the i group. The experiment was repeated in triplicate