Fig. 1: Schematic illustration of the fabrication of biomimetic bubble nanomachines with small-scale nanovesicle secretion for synergistic photothermal/photodynamic therapy.

a Design of temperature-responsive biomimetic nanodevices by cloaking 4T1 cell membrane onto PFO/Hb-loaded AuNC with oxygen pre-saturation (ICG@CCM-AuNC-PO₂-Hb). The inside abbreviations [AuNC] =Gold nanocage, [PFO] = Perfluorohexane, [ICG] = Indocyanine green, [ROS] = Reactive oxygen species, [Hb] = Hemoglobin. b Laser-triggered nanovesicles secretion for enhanced tumor penetration:, (1) Homologous tumor targeting of ICG@CCM-AuNC-PO₂-Hb based on the cloaked 4T1 cell membrane; (2) Laser-induced photothermal therapy of ICG@CCM-AuNC-PO₂-Hb; (3) Hyperthermia trigger the evaporation of inner PFO under NIR irradiation; (4) The gaseous PFO extrude the cloaked cell membrane for the formation of biomimetic nanovesicles (ICG@CCM-Hb); (5) Penetration of the generated ICG@CCM-Hb with smaller size into deeper tumor region; (6) ICG@CCM-Hb deliver oxygen into deep tumor for self-sufficient oxygen-augmented photodynamic therapy upon second laser irradiation.