Fig. 1

Characterizations of the prodrugs and prodrugs-loaded liposome. A Prodrugs transformation at different incubation times and concentrations of H₂O₂. The PBSN38 and PSN38 were separately incubated with 0.05 ~ 5 mM H₂O₂ solution with the prodrug and H₂O₂ at a molar ratio of 1%. B The size and zeta potential of CPBSN38L measured by dynamic light scattering (DLS). Morphology is shown as observed by transmission electron microscopy (TEM). Scale bar = 100 nm. C The kinetic of SN38 release from CPBSN38L in a PBS solution containing 10% FBS and 2% glycerol without and with H₂O₂ by using a dialysis bag at room temperature. D Quantitative results of the flow cytometry analysis of the intracellular ROS levels in MC38 colon adenocarcinoma cells treated with PBSN38L (blank group), PBSN38L + DCFHDA (background group), CPBSN38L + DCFHDA (CPBSN38L group), and CPBSN38L + US + DCFHDA (CPBSN38L + US group). E Flow cytometry assay of different acoustic intensity-induced ROS production of CPBSN38L. F Representative flow cytometry plots and G confocal laser scanning microscopy (CLSM) images of the intracellular ROS production of CPBSN38L. MC38 cells were incubated with CPBSN38L for 4 h and detected by DCFHDA staining (green). Scale bar = 50 μm. The data are presented as the mean ± SD (n = 3)