Fig. 4.

Human ADSCs-Exos adhesion to PLGA/Mg-GA MOF scaffolds. (A) Zeta potential evaluation in exosomes, Mg-GA MOFs and mixtures. (B) The nitrogen adsorption−desorption curves of Mg-GA and Exo-Mg-GA. (C) The PKH26-labeled exosomes were attached obviously different to the control (PLGA) and PLGA/Mg-GA₂. (D) Scanning electron microscopy (SEM) showing nanoscale roughness on PLGA/Mg-GA₂ surfaces from exosome coating. (E) Schematic showing immobilized exosomes on PLGA/Mg-GA MOF scaffolds via electrostatic interactions. (F) Cellular uptake assays showing PKH26-labeled exosomes were internalized and distributed in the perinuclear region of HUVECs. HUVECs were stained with DAPI (blue) and exosomes stained with PKH26 (red). (G) Cellular uptake assays showing PKH26-labeled exosomes were internalized and distributed in the perinuclear region of hBMSCs. (H) Exosome accumulative release using the micro-BCA assay at days 1, 4, 7, 10, and 13. Data are presented as the mean ± standard deviation (SD) (n = 6, *P < 0.05, **P < 0.01).